Hi, and welcome!
I joined after buying a GTI too, very similar spec to yours but no sunroof, although I do have the winter pack which is great.
My early thoughts on the car are here;
http://www.uk-polos.net/view ... 56&t=62005
I've done a few thousand miles since then, and I'm still really pleased with it.
I disconnected the sound actuator, as I found it boomy and intrusive, and without it I can hear the supercharger more and the metallic and real howl of the engine at high revs is better in my view than the artificial sound actuator. I sometimes reconnect it just to check I prefer it without though!
My mpg has settled down to around 38mpg with a mix of rural roads and hard acceleration/fun, and can get over 44mpg on a 200 mile run.
Oil wise, I did have initial concerns over consumption, but with my driving style/journey patterns it has settled down to 1 litre per 2800 miles, which is more than I'd like and more than any car I've ever had, but it's well within the VW tolerances. I don't mind the fresh oil going in between services to be honest!
Performance stock is good, but with my TMC box on is excellent, I really notice the difference after 2100 rpm and it really pulls from 4500 rpm.
I came from a 265bhp Audi S3, and was worried I'd find the performance a bit lacking after that, but being a lighter car it doesn't feel all that much slower although it undoubtedly is I guess, even remapped. The main thing is, it isn't slow in comparison to the majority of cars on the road, and nor is it boring.
I've lowered mine on Eibach pro springs, which look better than stock, without looking too 'boy racer', and I've replaced a rear stock shock absorber which sprung a leak. I'm going to change all the shocks to Bilstein B6's soon I think, and keep the springs.
I'm also running a set of winter tyres at the moment, and the traction and particularly braking on snow and ice is excellent compared to the stock Dunlop summer tyres, I don't miss my quattro so much now. I'd highly recommend a set anyway.
Overall, nearly a year into ownership, it continues to impress me with its ability to be easy to live with whilst being playful when you want it to be. Very practical too, plenty of room in the back for my daughters baby seat.