I don't care if it is mp3's or 24/96 wav...

What we are talking about primarily is the willingness to play over an audio file, and, in my case, more particularly, an audio file that you had nothing whatsoever to do with the creation of...

There are two weaknesses of using audio (at least!), the first, and probably primary one, is that compared to either styles or SMF's, you have minimal editing possibilities. You can't mute a part, you can't make it louder or quieter, you can't apply an effect to it... Everything you do to the file affects everything. Got a guitarist sitting in? Forget muting the recorded guitar solo. Someone playing congas with you? They are going to have to play over the existing conga part. Want to change the feel of the track (swing it a bit, perhaps) after having played it until you are sick to death of it always being the same? Best of luck, mates.

All easy to achieve with SMF's and styles (and pretty common scenarios to all but the loneliest of the lonely OMB's)

Secondly, as I've mentioned before... You have a repertoire of hundreds of mp3's. You change arrangers, for one with a far superior sound (no point in changing, otherwise, eh? ). Your act still sounds essentially the same. And, even if you DID make these mp3's from your own playing and SMF's, rather than buying karaoke tracks, you SURE don't feel like re-recording your entire repertoire, so you end up playing primarily with older gear you have long sold...

Curiously, the ONE thing I see as the strength of using MP3's for seems to be the thing most use the least... The opportunity to hire a REAL guitarist, maybe even a real drummer, and prepare backing tracks that are REAL... but YOU did them, so it's still not commercial karaoke, and your act is your act, not you singing over the same stuff everyone else is. Very few doing this, AFAIK.

But whether the delivery medium for audio tracks is mp3, .wav, .aiff, or some future system TBA, they will all suffer from these pretty insurmountable problems...