Here are some of the things I've tried:
1. ADAT's. Great stuff. The only thing is, they need periodic maintenance, and they WILL start munching tapes if they go out of calibration.
2. Hard disk recorders. Currently I have a Fostex VF-160 that I'm using to record rehearsals. 8 tracks of simultaneous recording, plus it has a "digital mode" where you can use the optical interface to dump 16 tracks at once from a pair of ADATs. Plus it has a built in mixer and CD burner.
3. A computer. This is really the ultimate in terms of flexibility and processing power, but you have to get a reliable one. Don't waste your money on a Windows ME system. I have Windows 2000 and an M-Audio Delta 1010, 8 digital I/O channels plus MIDI. I use Cakewalk Sonar on the PC, it's pretty good, doesn't have all the bells and whistles that ProTools does, but it's not ten grand either.
Ideally, some combination of the above. For instance, I lay down a MIDI drum machine track, and a bass and rhythm guitar track at home. Now I want my drummer to do his part, so I have to dump the tracks from a computer to the Fostex (with MTC, so I can time-lock the Fostex to the computer on the way in and the way out), take the Fostex over to the drummer's place to get my 8 track drum recordings, then take the Fostex back to my place and dump the drum tracks back into the computer, for editing and mixing.
Then frankly, computers can be a real pain in the butt when it comes to the initial "experimental" stages of a mix. All those digital controls can be quite painful, it's much easier just to turn a few knobs and dial in the sound I want, instead of mucking with digital parametrics and constantly having to undo and redo the EQ to get the frequencies just right. So for that purpose, I'll dump the computer stuff to ADAT, set up the mix in the analog domain, re-sample it, and dump it back when it's done.
It really helps to have that kind of flexibility. But if it has to be one and only one device, the first one I'd get would be the Fostex (or a similar device). It contains everything you need to create good quality audio CD's from up to 8 tracks of analog input.
