Depends on what condition your Mk3 is in, most I see now are nearing the end without major bills. I sold my 1998 MK3 VR6 last year, and bought a 2000 MK4 1.8T. I has the Mk3 for 8 years and loved it to bits kept it till the bitter end. Once it started to rust the arches it was in terrible shape after 12 months and it had to go.
Things I like about the MK4:
- Interior is MUCH improved, better materials used and better screwed together.
- Much quieter inside when driving, feels much more refined.
- Fully galvanised body, so not much rust
- Handles better than the MK3 (stock vs stock)
- Feels much more responsive
- Easily increase power with a cheap and quick remap
- Standard speakers are really good (MK3 ones were the terrible!)
Things I don't like about the MK4
- Feels a little gutless at higher speeds
- Its quite easy to make it look chavy, but I think the same can be said for the MK3.
- Its not my MK3 VR6
