GIAC questions, NOT vs.

So I decided to with Giac in the near future, just because I like not having to downshift in order to accelerate.  Im just wondering what boost I will be running with Giac, I assume 18-19 psi?  what about APR?  is AWE tuning the cheapest and the best place to get the chip? I would really like to keep my stock ECU  http://www.awe-tuning.com/pages/shared/part_detail.cfm?PMaI=1&PMoI=1&PEI=2&PP=a4_18t_chips.cfm&PPT=Chips&IL=GIACChips
Anyone know the changes in MPG comparing to non-chipped ecu?

The best place to get a chip is from a tuner to whom you can drive.  If AWE is close, go for it.  Price for the chip is pretty much the same everywhere.

The chips are about 1.1 bar or approx 16 psi.  Don't expect to hold that pressure to redline as the turbo can't push that much air.