I did my inital ME SPA IR at Stapleford at the end of last year. I'd certainly say the DA-42 / G1000 combo makes passing the IR a hell of a lot easier; it also prepared me (coming from a strictly steam-and-dials world) nicely for the MCC. As for the controlled airfield thing -- I'd say that's not even a factor. You're not in the circuit that much, if at all. Most of the time you're off on route flying (once you're out of the sim and in the aircraft). The only interesting thing is negotiating with London to get a join somewhere north of the field, but that's no drama.
I'd wholeheartedly recommend them if you're after an IR with minimum stress and a decent quality of training.