Here is a follow-up on the M-Audio AXIOM (only) controller -- I decided to take that one as opposed to the "Oxygen" model. I purchased the 49-key model (25 and 61 key available):

-- I like the keyboard feel, after all. It is somewhere between "synth" and "piano" feel, not as wonderful as a good hammer-weighted key set, but perfectly acceptable. And for the price, I think it's an achievement. The board iteself is solid and give a better impression than many of the ultra-lite plasticky boards available. Before finally deciding to keep the Axiom I also tried out a comparable Novation controller --- though it has some nice features, I found the keys a little more "synth" in feel, though others reviewing it disagree, praising the "semi-weighted" feature. I also again tried the CME UF series of boards; I like the look, feel and apparent quality, but the lack of any memory to save custom settings threw me off. The Axiom does have space for I believe 20 custom presets or setting groups.

-- The controllers (rotary and sliders and buttons) have all worked so far. I think the feel is acceptable. Many competing boards are really cheap to the point of making the Axiom and a few others stand out.

-- There are apparently various problems synching with various software packages. The "presets" may not be up-to-date for certain software revisions. I base this partially on bulletin board comments from others, as I have limited software and short experience with these. The "Enigma" software that comes from MA with the controller board appears fully-featured (it is basically for setting up the board in many variations and adding and modding presets). However it is less than easy to use, and I have had a number of problems trying to set up my board.

-- On the other hand, without getting into the full use of controller commands, I have successfully used it with OMB, OMB-Forte, MA Key Rig, and a few other things. I have not yet mastered the "drum pads" on the board, though they certainly seem useful down the road.

More feedback coming if I learn anything important.