As soon as he had mapped my M5 I had a knocking noise from the nearside cylinder head behind the VANOS unit, and I mean literally first turn of the key he asked if the knocking noise was there before, which it wasn't. Then a while later a big end shell span round the crankshaft nearly totalling my engine (four days before a Nurburgring and Spa trip!). During investigation we found that my car had a rasied rev limit which I had particularly asked Emaps not to raise as this is an issue with the V8's. Simon admitted to me that he didn't even know what the stock rev limit should be on my car and was not aware that my rev limit had been raised :headwall
I think someone who is selling maps should know basic things like rev limits for any car they work on. Emaps also used to (still do?) claim that their maps are custom, yet we found the exact same map on another M5 that was mapped by a different company altogether, not Angel Tuning as previously mentioned.
Credit where credit's due, I know a lot of people are happy with his work and I'm not blaming him for me rebuilding my bottom end. If the rev limit was raised without me knowing I sure as hell used it, but there are elements where I would expect more knowledge on rev limits etc... I used Emaps through the BMW community and the map was reasonable, but the end result was poor and I have another map on there by someone else and a stock rev limit which I am much happier with.
At the end of the day with remapping, just do an enormous amount of research on who you are using and what they can provide, especially if you have a vehicle that needs a bit more attention than normal. We also found one of Emaps maps on a customers vehicle a few years ago in our workshop which caused a warranty issue and some time to resolve, and I think Emaps used to claim that their maps were not detectable? Not sure if anyone still does claim this really.
Please don't take the above as me trying to destroy someone's reputation because I'm not, but everyone needs feedback - good and bad!
cheers