afcjay,
Your 1.8T A3 will have the smaller turbo, so it by it's nature provide a smooth boost/power after a remap (unless you go to some cowboy, doesn't know better). I had a remap on my old A3 1.8T from JabbaSport and it really transformed the car pretty much all over the rev range.
They RR'd it after and gave me a figure just under 190bhp, which I took with a pinch of salt, but driving it home I did notice a lot of extra "eagerness" and faster acceleration.
I've got an S3 now and it has the bigger (K04) turbo, which needs more revs to spin up. After a remap by VAG Check (very good guys and highly recommend their stage 2 map) the turbo on the S3 gives manic acceleration above about 3200rpm, and that gives you a bit of a kick
I can't imagine what the bigger turbos feel like.
With turbo cars, most of the remap's effect is felt once the turbo kicks in, which for you would be just under 3000rpm, but it feels good all over with added bonus if better fuel economy if you drive gently.
Most tuners give you a trial period/money back guarantee after short period by uploading your standard map back to your car if you are not happy.
Definitely go for it, you will not be sorry