Synth Site |  Boss |  DR-202 Dr. Groove

The main drawbacks I see versus the DR-660 are the non-velocity-sensitive pads, the smaller display and the lack of 1/4" outputs (stereo RCA only). But in exchange, you get more useful sounds (for my purposes at least), nifty realtime resonant filters and effects knobs, and of course the bass synth. The preset patterns all sound like shoe commercials to me, but I'm just getting started making my own stuff.

I haven't played with an MC-303, but from what I hear I'd much rather have this one, as the MIDI implementation (a common gripe about the MC-303) seems surprisingly extensive. This is apparently meant as a companion to the SP-202, and it looks similar as well (somewhat 808-like). The sequencer is 3-track (drum, bass, external), and all the knobs actually send realtime data over MIDI, making them much more useful. It does get velocity/aftertouch through MIDI as well.

It has all the usual drum machine programming features (groove quantize, roll/flam, step/realtime recording) plus portamento for the bass section. The buttons do feel a tad cheap, and the display is not backlit, but man those knobs are fun.