I had an M Audio radium 61. Great functionality, horrible plastic feeling keys and board. A37 feels fine to me, but I too would like a USB version.

I haven't tried the Korg Kontrol yet, but 49 keys isn't enough for me anyway, except when I'm controlling and analog synth or emulation of one. The microkorg controller was very functional, but the minikeys killed it for me.

Let us know what you decide to get and how you like it please.

AJ