The same engineer who designed the original DFI also designed FAST and now Bigstuff3. I don't think you can go wrong with any of them, even the new haltech stuff is pretty nice.
I went with FAST XFI because of it's popularity, and all the tuners around me know how to use it. Fast also offers a lot of high quality parts and addons. I am using their Edash, pressure sensors, and boost control solenoid.
If you decide on FAST, I think I remember enough about the install to be a resource, I can also send you my tune, it might make a decent base tune.