I personally was not a big fan of Cartek way back in the day (mid-'00s). For a number of things, but up near the top would be Julio tuning my still pretty new T/A while smoking a cigar in it. And I enjoy a cigar but wasn't particularly happy about that. Locking the PCM would be another. Crappy customer service unless you wanted to drop 5 figures on their heads/cam packages and them doing all the work.
Only ever dealt with Complete Street in West Chester and ECS way back in the day (mid 00s as well...) when they tuned and dyno'd my cammed f-body. CSP did the DOD delete in my PPV and tuned it and I was very pleased with both the price and quality of their work. ECS I can't recall being disappointed with anything either. Don't know where you are located relative to each but I'm in Essex county and either shop was not appreciably far away. Good luck.