I have the SCT SF3 - this tuner comes with pre loaded tunes for our cars. While its not a custom tune, the program was tuned with a bolt on mustang. I love it! Im not sure if the xcal has trans shifting functions for auto's but I know the SF3 does. SCT is also better IMO because there are a lot more tuners out there more familiar with the program. They also fixed my tuner for free when it somehow got locked up?? The bad is its married to the PCM, and they charge $60 to unlock it. But if you only have 1 car that needs a tuner then its no big deal. Xcal is also a good tuner. What I did is took the preloaded tune from SCT, then tailored it using data log. Runs great! If I had to do it all over again, i'd go SCT Pro Racer Package. I have heard tons of good and only 1 bad from a guy on the corral. Pro Racer skips paying tuners and you can control everything! Not sure about sniper's software, but im sure I hear good things.