Any vocalists here ever try one of these?

Nope it doesnt. But the programmable harmonies on the other unit are NOT easy to program. Its definitely NOT something I would want to use live.

If you are planning on using it for your Floyd Tribute band, I would think strongly about just training your bandmates to sing background vocals. LOL

This is just my opinion though, go down to Guitar Center and spend an hour or so messing with the thing and maybe you might like it.
 
I have lots of electronic toys, it should be no problem. What's great about the Helicon is the voicing, great warm sounding reverbs and delays. You can plug it into a midi keyboard then even if you sing off key it automatically puts you in key. Can't go wrong!