I'm new to this board, but I have done lots of tune R&D. I have both Ion and Bryan for my 94 Impala SS. Both were very comparable. I also use Tunercat to do some of my own adjustments for shift points, etc. When using tunercat, you can "compare" files and see any differences in the 2 tunes. So I kinda took both, used one's engine tune and the others tranny and speedo tune...voila'. runs real good. Actually, for the cost of unlimited tunes from both programmers, the cost of one PCM repair from Ion and the cost of tunercat w/ def. file was still less than LT1 edit.
Just my $.02