A3 Potential Buyer Questions

Hello there I'm really set on an A3 now think they are great, driven a few at work and like the look and way they drive, so want one of my own! And it's an Upgrade in the VAG group from SEAT lol

Anyways here begins my questions, sorry there are a few I'm looking at the 2.0 diesel options, whats better to go for a 140 brake or the newer 170? Is the difference between the above bigger injectors, remap and the DPF? anything else?
Just i can get a more for my money with the 140 obviously!

Also DSG is it worth the extra? I've always been a fan of manuals over autos, i like to downshift and engine brake, but will this fox the DSG box?

Quattro also i'm assuming this makes the world of difference to the handling over the FWD version, just after a reinforcement of what i already expect lol

I'm looking at for a used S Line preferable Facelift model, as a general rule the facelifts seem to be post 06 registration

Again apologies for the newbie questions

Thanks Tyler

Thanks for the reply .... the remap is a given i work for a tuning company

I've decided that i'd rather have quattro over a DSG box

Going to look a couple tommorrow looks like i'm gonna have to go for a 140 as the quattro 170's are still abit above what i can realistically afford

Gonna see how it goes tommorrow on a test drive, still looking at the idea of owning a diesel is pretty new, always been a petrol head, but after driving a few mapped dervs via work and moving into the london from the countryside, and discovering a thing called traffic i think a diesel is a more viable option especialy as there isn't a chance to use the extra revs of my 1.8T ....