ORIGINAL: forestroke
BUT... isn't a lot of dihedral an automatic levelling system? i know many trainers that releasing the sticks basically levels the plane. the larger the dihedral, the larger the righting force. now, does a trainer with large dihedral = a crutch? i think not! in fact, back in the 3 channel days, all planes were self levelling. difference was that you couldn't easily take that stability away.
That's entirely true, and maybe having a crutch isn't always a bad thing while learning. Of course... When was the last time dihedral caused your plane to get confused about which was was up and flip the plane over?
That being said, the sensors are usually directly attached to a custom receiver in an rtf plane. I've seen it for sale as a separate unit, but can't remember what it was called. It's probably a bad idea for any plane that isn't going to spend 100% of it's time flying straight and level though. Otherwise you'll be fighting with it constantly. That's why they're normally only on trainers.