Hi from northern Tasmania

Hi Ben

Hi Ben,

The Io is a great choice, I also searched for a good small 4wd and ended up choosing the uncommon choice of the Io. I lived in Hobart for 18 months and found my Io was great for trips away esp in the snow!

I was looking for a daily driver that my wife and I could take camping that was still capable off road to the point of not needing to rely on others, but without the V6 or V8 bulk and fuel consumption. Many people tried to convince me the Vitara was better due to accesories however the Io is a superior vehicle in all respects.i drive 60kms each way to/from work on country roads and motorways and The Io is very confortable on the highway at 120km/h with good power for overtaking etc. I agree with your appraisal of the Jimney - they are a tarted relic from the 80's and even make the late model sierra look good. 

I'll answer your questions below

"1. Exactly how does the iO's 4WD system work? If my understanding is correct, it uses some form of viscous centre differential which - like the more recent full time 4WD Land Cruisers and unlike the Suzukis and most traditional 4WD setups - allows 4WD to be selected and used on road without causing transmission bind up. Where I live - especially in winter as it is now - is notorious for bad weather and bad, slippery, icy roads. The option of an on-road 4WD mode would be a plus."

The 4wd system is the same "super select" as the bigger pajero's. Simply put you have a shift lever behind the gear lever that can shift between 2wd (rear wheel drive) and 4wd (constant 4wd) on the go under 120km/h. The Io has a proper center differential and does not use a viscus coupling. The front diff has a vaccume connect to engage the front hubs so in 2WD you aren't pushing along the added 4wd drivetrain. The power to the front prop shaft is via a heavy-duty chain drive the same as the bigger pajero's and is massivly over engineered for the tiny Io. I used the constant 4wd around hobart, mt wellington and mt field when I lived there in winter and it is really well balanced like a subaru, great for icy conditions.
You can push the stick forward into 4wdlock which locks the center diff, (shift under 30km/s or it crunches). further again drops you into low range + center lock which is a 1.5:1 ratio, not a rock-crawler but more than sufficient for a small 1.5t 4wd. I was concerned about not being able to choose low without center lock but since I've owned it (3 years) it has never been a problem.

"2. Did only the Wagon/LWB versions get the LSD in the rear diff? Is the LSD worth its salt off road?"

only the LWB gets the rear LSD. I drive a SWB and have never seen the pajero LSD in action. There is a video on here of one of the guys with it going but like most LSD's only gives you a minor amout of bias.
I have an ARB air locker fitted I the rear of my Io and rarely use it except in the most extreme situations where I will be up on two wheels only e.g. crossing large berms on the diagonal. Honnestly i doubt you'd miss it if you got a SWB.

"3. What is a reasonable aim in terms of suspension lift and tyre size? My 4WDing aspirations at least for the short to medium term are moderate and as the car still needs to be behaved onroad I do not wish to lift it halfway into the sky either! I do however want to be able to fit decent all terrain tyres (I may run separate sets of on road and more serious off road tyres if the budget allows in the future) and get a reasonable amount of clearance under the vehicle as a lof the places I will be going to are very rocky. My understanding is that a 2" suspension lift is reasonably easy/affordable to achieve without destroying CVs or shock mounts, etc.? What tyre size does that realistically allow?"

there are threads on here about this as well, I'm only aiming for a mild lift of no more than 2". Stock tyres are 215/65-16, fitting 215/70-16's correct the spedo error and 225/75-16 would be right on the maximum that would fit under the front spring perch i.e. only a few mm clearance - no room for mud etc. You can put lift springs in the Io but it the front struts that limit massive tyres. if you want to run snow chains on the front wheels run stock tyres or move the spring perch as you only get 1.5" ish between the top of the tyre and the perch.
You can lift the front spring perch and lengthen the front struts easily enough as well as space the front diff down to reduce CV angles if you want to put some effort in, but even in standard height  with 70 profile tyres they perform very well.
I bought some michellin lattitude cross tyres when I arrived in Hobart and found they handled the wet cold roads at highway speeds in silence and the sharp quartzite tracks of Gordon area really well.

"4. How flat is the underside? Is the transfer case, etc. properly tucked in or does it stick out like on a Hilux, just waiting to grab a rock? ;-)"

the underside is not perfect and could definitly be bullet-proofed with extending the front skid pan  back to the gearbox cross member however it is by no means as bad as the hilux. The gearbox crossmember is very very strong but does sit lower than the sills and I've rested on it a few times. in the SWB the bottom of the transfer box is right in the middle of the wheelbase and even though it is near flush with the sills it is where I generally kiss the ground when climbing up and over things, though in all cases it came down to me not picking my line and trying to follow in the wheel ruts of bigger 4wd's. I've thumped it severly a few times with no damage apart from chunks of clay/rock sticking to the outside of the box.
I have snagged a log that was hiding in the grass in the middle of a logging trail at high speed in the florentine vally one night and it collected the fuel tank bash plate smashing it back against the tank however no damage otherwise. I was late and driving over 100kmh on a track that should have been taken at 50kmh.

"5. Anyone running a dual battery setup? I will probably fit a winch at some point... just looking at under bonnet pics, there doesn't appear to be much extra space for a second battery tray."

No - you won't find any additional space for a second battery BUT you can fit a fairly big one in the standard spot. I have a 700cca battery from memory, was a case of measure up the gap and then prowl super cheap auto til I found one that fitted the bill.
I was searching the engine bay or room to mount a compressor but under the front seats is going to be the best bet OR on the LWB you might tuck something inside the rear pannel but you'd need to vent to outside etc. As archaic as this sounds I'm acually fitting a crank-handle to mine should I run flat.

"6. Where's the best place to get modification parts? Obviously being a rarer and not as oft-modified 4WD as Cruisers, Suzukis, etc. I can only presume the amount of the off-the-shelf bits available is fairly limited."

All depends on what you are after, if it's a bull bar then East Coast bars do a few, suspension lift parts through Dobinsons, Koni make after market strut inserts and shocks and KYB make struts. Airplex in NZ do headlight protectors/bonnet guards and Wildcat Headers do extractors. ARB only do the air locker and mine was the first ever in australia to have it fitted, it'snot in their catolog but drop me a line and i can tell you which model they use. "Ultra Racing" in malaysia make all manner of strut braces, roll bars etc and are easily bought thrugh ebay.

Not sure what other mods you'd need? I've not seen any cargo barriers but havn't really looked hard. No one makes a winch bar due to the airbags but there are plenty of online photos of guys welding their own. Ebay searches for pajero io and pajero pinin will bring up all the minor mods you'd want as the io (pinin) sold well in europe and UK.

I chose the SWB as I didn't want anything too big and couldn't justify the environemtnal impacts of excessive fuel consumption. When my wife and I to go car-camping there is just the right amount of room for about a fortnight. You _can_ unbolt the rear seat and seat cussion to make the rear area flat, we don't do this however when I do the simpsonnext  I'll be doing this so that I can cargo barrier it, bolt in a fridge and a second spare.

Hope this helps answer your Q's. While I was in Hobart I hooked up with tassie 4wd club and did the jeffires track in heavy mud. everyone in their ultra-modded patrols laughted at the hairdresser comming along but I was the only non-ultra modded 4wd to make it up the southern hill and though the boulders without issue, and i was the ONLY stock 4wd on the trip. 

PS The 2L "ZR" model is the pick of the group and produces more power than you'd ever need while I found the 1.6L LWb undr powered when i test drove one. Definitly keep a look out for 2L models.

Bob