another newb to the site..
S4 Avant.. Mbox..
whats up kyle...

anywho.. my 2 cents..

I have had AMS, GIAC, and APR.. and have driven MTM.. currently have APR...

if you want a no nosense drive it all the time chip AMS is the best hands down.. I had nothing but issues with GIAC, they even wrote new code to address the issues I had.. the old code was really fast, but my car had throttle cut like a bitch.. the new code was weak sauce comapred to AMS.. in the end I traded my GIAC box for APR.. if I could do it all over again I would get the AMS box. it was the best driving hardest hitting of the bunch.. MTM is a great chip as well but it falls off up top.. imho its the hardest hitting down low..

anywho.. GIAC is the easiest to get.. go to the local dealer and they flash your ecu... done... I had the old stock 93 100 flash.. 100 was crazy fast compared to stock.. but my drivability was crap.. the new code ramps up boost slow compared to the others.. but I just dont feel right recommending it. honestly I know another person with the GIAC and he had to run a MBC in parralel to get it to run ok.. and every now and then he gets throttle cut.

anywho AMS gets my nod. you can get a borla exhuast pretty cheap to.. saw them on ebay for 650ish shipped...

APR is a solid chip.. gets good gas mileage comapred to GIAC, and I like being able to switch on the fly.. but it doesn have the oomph giac and ams have...