I've got a 200, 1.4 16V.
It's been modified by the previous owner; lowered, colour coded body, MOMO wheels and front and rear spoilers. (it looks nice, honest)
People on these forums slate Rovers - it's fashionable to do so. Indeed, I'd bet most people on here haven't even driven Rovers, but as is the case with most forums just state what they've heard by the few.
As for reliablity issues; I've owned it for just over a year now (it's a T Reg) it's only ever failed me once. That was electric coil failure and due mostly to me driving in a very spirited fashion over a VERY bumpy road at 6k RPM.
Make sure you go for a 16V model, as the 8V's are a little slow. The 1.4 is 103bhp and the 1.6 nearer to 120bhp, which means you've got a lot more power than many other cars in its class (saxo VTR = 98bhp, Honda Jazz = 88bhp edit: Okay, Honda Jazz isnt in its class... but its faster than one anyway...etc etc) For a 15 year old design, I dont see an issue here? Oh, and as for this head gasket rubbish, yes Rover's do seem to have an issue, but from what I can gather this seems to be a problem with the larger K series engines (1.8's)
Rover 200's are a bargin atm, You're looking at £1300-2000 for a car thats cheap to run and insure. The only car close to that kind of value for money is the 306.