My mate has had his TM HK416 upgraded by them and after using it I decided to buy a Recce rifle and get the same work done on it. I've still not had a chance to use my Recce rifle though as I don't have the money to finish off the build just yet.
Sam, the owner is a really nice guy but he can be a bit hard to get hold of. Although in fairness i've found this is true of a lot of shops i've had dealings with.