I've said it before, but I'll always go to JKM for my car stuff - even when I moved away from the area I still make the trip down, take a day off work or whatever if I need to. People at work think I'm crazy, but I just tell them that good customer service is hard to come by, and you know when you get treated well! It also helps that they know their stuff too, they live and breath it
With regards to my mapping - I actually wasn't about when they did it - I was in town shopping! And with Revo, being a "generic" map (loosely termed) once it's loaded on, it just needs a test drive or two to check logs and tweak the boost/timing settings. I expect you may be able to go out with them while they do this if you want to - but you'd have to check with JKM yourself.
All that said, everything they did was explained to me, Keith did the mapping and told me what he had set it to, what the logs looked like in terms of CFs etc - I couldn't have asked for more really. Of course, you can always get the car on the rollers once done and you can see for yourself!
Hope this helps mate