It really depends on what kind of budget you're on. If you work primarily with ProTools, then I think the obvious choice would be the Digi002, which is absolutely fucking sweet. I've used it before and absolutely love it. A digital mixing board will be your best best in terms of flexibility and quality. If you need something versatile, i.e. something you could use when playing out as part of a sound stage/live audio rig, then go analog. But for studio work, digital is by far the best. Like i said, if you can afford it, go with the Digi002. On the other end of the spectrum, if you need the cheapest good quality digital mixer, the Tascam US428 USB would be a perfect choice. In between those two, I'd say go firewire if you can. Roland or Mackie would be good choices, as would Yamaha (though it would definitely be more expensive). Alesis is alright, but not my favorite, and I think that Boss mixing boards aren't all that great and tend to be slightly overpriced. If you're looking at just a midi control surface with no actual audio inputs, the Behringer BCF2000 is a wonderful fader-based midi control surface with motorized faders. Somebody say word.