Thanks for the quick search and reply, I've been out of the tuning game for a while, is RSC reputable. I suppose that's the bigger question here, who is reputable? I found some tuners but I've never heard of them.
The short answer is that practically none of them are reputable because almost every single one of them is in violation of the Clean Air Act and associated regulations. That is unless they have a CARB EO number and/or an EPA Certificate of Conformity for their calibration (tune). So it’s mostly a gamble. Do you feel lucky?
https://www.epa.gov/enforcement/clean-air-act-vehicle-and-engine-enforcement-case-resolutions
Also no matter who or what is to blame, if you have an aftermarket tune and you experience some sort of catastrophic engine failure, don’t expect the vehicle manufacturer to cover the repair or replacement under warranty. It’s too easy for them blame the aftermarket tune. If you think you can fight the lawyers and expert witnesses working on behalf of the manufacturer in a Magnuson–Moss Warranty Act lawsuit, good luck. You’ll spend 10x what that replacement engine costs and still lose in court. Can you afford $23k to replace that supercharged 3.0L V6 if it fails whether caused by LR defect or an aftermarket tune with less safety margin?
If your tuner offers supplementary warranty coverage, ask them for proof of how many times they’ve paid warranty claims (most won’t say because it’s confidential business information and gives the customer too much insight into sensitive company financials and they can make assumptions about product reliability). Then ask for testimonials from those customers that filed successful claims under their supplemental warranty (most won’t share that info either). Actually talk to those customers and learn what their first hand experience was. You might be surprised.