Reviews-wise, here's what I found:
http://www.rctech.net/forum/electric...g-systems.html
http://mini-zracer.com/forums/showthread.php?t=30831
Seems to work much better than most of the other IR ones - in that it will work through some paint, and will work in full on sunshine too. Couldn't find a bad review anywhere.
I just don't really see us being able to pull together the cash for an AMB system, particularly given that PTs are so insanely expensive. This seems like a good alternative!