Good choice.
They are very reliable, and tough to for a little car, stand up to attacks from much bigger cars very well.
There are a few known problems, mostly small and easily fixable at home.
Wandering Idle - usually a gunked up throttle body, fixable with some carb cleaner
Clutch problems - pedal box breaks easily, this is an expensive
problem to fix, but doesn't seem as common on Arosas as on Lupos.
As for living with one - I have a 1.0, which is very capable. Its not going to break the sound barrier, but we happily nip around town, and sit at 70 on the motorway. Boot space is nonexistant, but put the back seat down and you can fit mountains of stuff in there. I've taken 4 people, plus luggage, chiristmas presents and a few cases of wine through Germany and back; moved out of Uni halls; and slept in the back of mine
Seats are comfy (from what I remember, not had the original ones for over a year now), my one gripe is the accelerator pedal can be uncomfortable on long journeys - but that might be caused by my seating position (the seats are mounted very low)!
Fuel economy will depend what engine you have, but a tankfull will usually get you between 180-
280 miles. That tankfull is about 25-30litres
Mine has survived attack by: Van 1, deer, badger, van 2 and lampost! Still going strong
Oh, and they look lovely after a few careful mods
Anything else?