I had a custom tune on my sct chip, it worked. I got frustrated with not being able to do anything with it without paying someone to do it for me. So, I am learning how to tune myself with a Moates.net QuarterHorse, the Binary Editor, EEC Analyzer, and a wideband. I could have purchased the pro racer kit from SCT for like $800.. eff that.
I had the tune from my SCT chip pulled from it and I put it on my new QuarterHorse with the Binary Editor software as a base for whatever I end up doing.
So far I like it, but the learning curve is steep.