My previous car was a MK3 GTI. Great car, covered 60,000 miles in it (130,000 when I Sold it) They have funny querks but I work on my own cars and so fixed it myself. Rear Discs can be an absolute pain to replace, but overall easy to work on. They ain't quick and handle like jelly but there's something about it, feels solid. Having said that, I wouldn't pay that money for another one, but the 16v engine is not as reliable as the 8v. Watch out for rusty water hoses, rust around the rear window and side windows (5 doors are better than 3 in that respect)
Oh, dodgy relays can affect the fuel pump, so watch out for cutting out and the dealer not knowing how to fix!!
Nice car.... but I don't miss it now I have my Mk5!