I am not presently using it, but have one and have used it lots in the past with my 72 Cheyenne/20 with a TBI 350.
Craig is a great guy to deal with and spreads a lot of helpful info on thirdgen. Was happy to answer my questions before I even ordered anything from him and shipped damn quick on the 2 orders I've made so far from him. I originally had a 1227747 that I used a mastach serial aldl reader and ostrich with, realized that the bitrate on the 7747 was way too slow to do any real tuning and repinned for an 8625 ECM as recommended by the guys on thirdgen, I was real happy with the setup but my engine was toast (burnt about a quart of oil per 100 miles by the time I was done beating on it) and I sold the truck. I still have the 8625, an ostrich and PP2, and some day will put it to use in another truck...