IMO B5 quattro all the way! If you want to upgrade it then definitely want a 1.8t as well and a Manual is also a must for me. I have a 99.5 2.8 quattro manual and I love it and I still haven't had it long enough for snow. I would just get the quattro just to know that you have it. As for the B6 they should be just as good as the B5 I just like the B5 trunk a lot more.