From the research I've PERSONALLY done before going this route myself it has to be James @ RWTD! Remember, no ones tune is bulletproof and every man makes mistakes! How do you correct on this and ensure that you've got a quality tune? Get a dyno run and have your A/F checked ASAP! Good Luck
Rick at Amazon Racing is great. He's fast and he was right on the money with my tune. I couldn't be happier and I will go through him for future tunes.
No doubt go with James @ RWTD, he runs a top notch shop and will answer any questions you may have. However, keep in mind if a tuner is good he will stay busy, you should look at this as a good thing. Just my .02