I have a Jimny.
It's built like the proverbial - always goes through the MOT.
Like any 4X4 they can roll over if thrown round corners. Because they are small and 'cute' people treat them like town cars and hurl them around, which is why they got a bad reputation for rolling.
For on road driving don't expect to get anywhere fast. They are bouncy cars, but I don't mind that in the slightest. They are not towing vehicles, mind you. You can get tow bars for them, but they only have a tow weight of 1 (or is it 1 1/2?) tons?
As for off road, they are probably the cheapest true off-roaders (better than the pretenders like RAV 4s and the Daihatsu Terios - not true off-roaders). In that respect, the Jimny punches well above it's weight as an off-roader. So long as you've got off-road tyres, of course. When we had the snow down a nearby neighbour's BMW X5 got stuck in the snow. I drove straight around him! The Jimny is a surprisingly good off-roader (within reasons, of course - it's not a Humvee, after all). THere was an episode of Top Gear where they had to drive through a South American forest. Richard May used a SJ413 (the Jimny's predecessor, and basically the old model Jimny before it got new bodywork and a new name). It did everything the Range Rover did!
I love my Jimny. Best car I've ever owned, even if my girlfriend has nicknamed it 'The Tonka Toy'.