Looking for a USB/Firewire 4 track mixer/audio interface for live performance...

Hello everyone. I'm pretty new here, but am thinking this is the best place for advice as alot of people here are working DJs/live performers...

I'm looking seriously into getting a Vestex VCM-600, but will need a new audio interface to go with it (my Apogee Duet is strictly for studio use really). So, as I was thinking, I'm wanting a live singer/mc with my live performance that is closely linked to my set... So I'm wanting an interface that can handle a mic or two.

I've been thinking before that actually a little 4 track digital mixer (that is actually USB/Firewire and an audio interface) might be the best bet. But I don't know too much about them...

I was looking at this the Alesis Multimix 4... But was curious about latency and sound quality really. I'll be using Ableton Live to do my stuff, to do live producing basically (rather than straight mixing tracks).

Would this do me? Is there any other solutions for this sort of thing?

Check the Korg Zero family, maybe discontinued (actually nobody can tell this 100% sure) but even if it is true, both mixers are great (Zero 4 and Zero 8), I own Zero 4 and I am very happy with it, go check them out!