a md will record faster than a dat??? sounds weird. but i don't have enough experience in both to know, but sounds well.. not right.. i'd say that you wouldn't have much delay if any from running it as is, sound travels fast, i'd try to test it, before the show, like if the're runnin just some music, good chance to find out i guess. if all else fails the mono idea will work, just wont have any stereo separation and will make it sound boring. unless you take your mono track and put only the slightest delay in each L&R channels, you can get some stereo effect i've done this with voices recording for a better than mono sound. i'd just run mics to record that way you get some of the acoustics in the room, i always like that but thats just me, although matrixes are always really cool too.. good luck.