Recently moved from a 2.8Q to a B5 S4 Myself a month ago, great move, nothing wrong with the 2.8 by any means, it's just that the S4 is in many ways a completely different animal, particularly in the areas of handling and braking, my 2.8 brakes were never much to write home about.
My 2.8 had Audi sport suspension package from new, but the S4 is superior in all aspects except ride quality, which can be a little choppy at times
I suspect that the 1.8T B6 will be similar in feel to your 2.8, but with a much more upgradable engine
S4 is now AMD'd and milltek'd, instant hop to 320hp now want more though, and with regards to fuel consumption my S4 is no worse than the 2.8 on run, but far better round town, i guess it does'nt need to work as hard, but run them turbo's hard and it drains, still everything has a price.
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