That's a very handsome Presonus !
I do have an Alesis Multimix 12 connected to one of my computers. Much cheaper. Not sure they sell the 12 any more, but it works fine. Its firewire and can send all its outputs to the computer and receive a pair to output to your amp/monitors/headphones. Also has some basic effects. May not be the quality you are after, but excellent bang for the buck and very handy for live gigs.