I'll add my bit here...
- Basically the (non Cross) 4x4 and Cross 4x4 have practically identical off road ability. The only things the Cross gains are Hill Descent Control (only really needed for going down slippery muddy slopes of 30 degrees or more where you might prefer not to use the brakes), and a tiny increase in off-road height through (as you say) slightly taller tyres. The approach angle has never been a problem on my regular 4x4 - the Cross has a bit less bumper to catch, but maybe at the expense of a bit less protection for the intercooler? TBH, if either bumpers were hitting the ground your probably trying to climb
something the Panda isn't really designed for (it was, of course, really more for snow-covered mountain passes rather than off road trialling).
- The thing with the propshaft bearing: the propshaft is in two sections with a universal joint between them. This is supported in metal bracket (protected in a metal cage under the centre of the car) by a rubber 'doughnut', and a bearing in the centre of that which the shaft passes through. It's not the bearing that fails, but the rubber ring holding it (academic since you can't replace one without the other).... the issue is if the rubber perishes, it's then an MOT fail. The perishing seems to happen more in low-use, low annual mileage cars. Mines done 44000 miles in four and a half years and that part looks new still, but I am quite festidious about hosing out under the car when it gets too muddy and after each road salting season - this seems to help a lot. It was starting to perish on my 2005 4x4 when I sold it in 2013... A complete new propshaft including that bearing is £260 (note: dealers want £1600!) , and easy (with the car on a lift) to remove and refit so don't be put off by horror stories on this one. (Note the propshaft is identical on all Panda 4x4s from 2005 onwards - although the part number changes now and again, they're all the same dimensions and interchangeable -
https://desshelleyshafts.com/produc...rand-new-55193595-55197051-55222107-55264146/ for example)
- I can't comment on TwinAir engine reliability - mine's a 1.3 diesel. I can say though, the diesel has 95bhp, and a useful 200 Nm torque at 1500 rpm (the TwinAir has 145Nm at 1900 rpm) and loads of engine braking, so I feel no need for Hill Descent Control on mine. Owing to the smaller torque at higher revs, the TA versions get an extra-low first gear in the gearbox to help with the steep stuff. The top gear ratios are unchanged. On the motorway at 70, I'm seeing 2800 rpm, and I think the TwinAir is around that same figure. Most of the din at that speed is wind noise (added to by my genuine Fiat roof bars) and tyre noise
- Tyres - yes, do check: the Cross 4x4 was supplied with Goodyear Vector All Season tyres from the factory (185/65 r15 size) - although after about 2017 they were all sent out on Summer tyres of a smaller size for some reason. Mich Cross Climates often fitted as a replacement... but if any sort of summer tyres is on the car that will knobble the off road ability quite a lot!
- clutch and dual mass flywheel; again, I've had no issues (this is my third diesel 4x4 and they all have DMFs), but as with all cars with a DMF (many - petrol included - do these days), avoid snatching gear changes and crucially, avoid labouring the engine at low revs. Its the latter that leads to the greatest risk of damage. There are plenty cases of them lasting for ever, and also others failing at low mileage - so mileage
per se isn't the issue, just driving style. Following the 'change now' light, especially the downward changes is key.
- something I don't think others have mentioned: there's a hefty metal under tray/sump guard on the 4x4 models, which is prone to rusting through, again especially on cars where mud and salt is not regularly washed away, and possibly more on low use cars as the trapped water doesn't get shifted from the tray. This tray should come off at every service (to reach the oil drain) but there are some folk on here who have found the bolts have rusted in place. The tray can be bought form Shop4Parts (Fiat specialist) for about £160 I think... but if not too bad, removing it and repainting with something like Hammerite seems to do the trick) - see this tread
https://www.fiatforum.com/threads/rusty-sump-guard.486312/