I have mk 1 , mk2 and a mk3. I really like the mk3 but have to admit it aint as quick as the mk2 and definitely not as quick as my mk1

however, it does depend on what you want the car for and to do! the mk3 is very comfortable and does everything you ask of it. i personally think the handling is ok and have used it on the track and it did not disgrace itself against the competition.
fuel economy also good from the mk3 compared to the 2 and 1.
i wouldnt be put off but you do need to determine what you want from the car etc...
thats my two penneth....