Look cheap....
They do look cheap and are prone to falling off if not securely attached. (happened to a drummer at a show i saw, took em 15 min to get it back on, funny)
I have used the DDrum red shot trigers on my acoustic set for a while now. The only problem i found was that the actual wires that connect to the head trigger are on the outside. so if you happen to slip or lets say you let someone, a guitarist who doesnt know how to play drums, thrash on your set and he accidently hits the trigger, good luck fixing it.
They do mount to the Rods so they are really sturdy and easily bent so that you can put them on almost any head rim.