Just to add my $.02 to this discussion...

I bought a set of Logitech Z-2200 speakers based on the comments here. I needed a set of computer speakers for my computer desk anyway and the possibility of being able to use them with my keyboards or with Reason was just an added bonus - plus there is a $50 rebate through October 31: Amazon.com had them for $107 (no shipping or tax) but I think they've raised their price to $109 now. The rebate is from Logitech so final cost is $57 or $59.

Well, for $57 these are very good gaming speakers with enough bass to piss off all of your neighbors handily. Great power, but with 2/3 of the power going to the bass and no real EQ other than a volume control for the subwoofer, these speakers are not good for music IMHO. I tried using Reason with it and got too much bass even with the subwoofer volume set for minimum. I tried my Yamaha 9000 Pro keyboard with them and got the same results - uncontrollable bass. Rolling off the bass EQ in my 9000 Pro helped but not enough to justify using this speaker system live. Wish the satellite speakers could be used by themselves. I don't think it's possible to come anywhere near a flat frequency response with the Z-2200's, but they weren't designed for that anyway.

Spec-wise and especially price-wise (while the rebate is on) the Z-2200 system is good for what it's made for - computer games. They would be clumsy and fragile for gigging and I don't like the muddy bass-heavy sound for music - I'll be keeping my Motion Sound amps, thank you very much. None the less I don't think a better computer-gaming speaker system can be had for $57, so I'm keeping them. Thanks for the info guys!