give us more info as to what you need to use it for. do you just need to monitor all of your gear or do you need it for tracking or mixdown or all of the above. do the 2000xl and ensoniq have the multiple outs options and what other gear do you need to connect to the mixer? are you going to take it out for gigging or just in the home studio? what's your budget?
in general though, you have 2 popular choices:
a Behringer ---> these are very cheap and a good first mixer.
or a Mackie ---> these are a little more expensive than a Behringer, but they seem to be built a little more rugged. a lot of people say that they sound better but as semi-pro models, there's really not much difference. Mackie's do have better mic preamps though, but with the gear you've got, you're not going to need them.
also there is the analog vs. digital thing, but with your gear, analog is probably the best way to go.
anyways, you're not going to get audiophile-sound quality without going to a pro studio or dropping thousands of dollars, but for a home studio or for gigging there's plenty of options out there.
if you need more info on types of mixers this dude has a pretty good guide (it's three pages long):
http://www.tweakheadz.com/choosing_a_mi ... tudio.html
