My build uses the Legato output stage so it drives balanced amps, not bridged ones (and I'm using a Dynamid - bridged Dynalo). It sounds amazing, even compared to the Buffalo2/IVY that I run in my main system; it just doesn't plug directly into my setup. I would have to install a volume control, add RCAs and install output caps for it to play well with my Dynalo if I want to replace the current. It was purpose built, so doing all those mods will be a bit of a hassle to suit my current system.
I've heard pretty good things about the OPUS, though never owned one myself.
The power switch is a Bulgin 250V/3A pushbutton switch with blue LED. One of my favorites at a great price.
Thanks for the information on the switch. I'm really looking forward to hearing your Buffalo 2/IVY build at the meet. If I like what I hear, my first purchase after the meet will probably be a set of Buffalo 3 SE boards. I get the feeling there will be other temptations aplenty, though.