Hi Steve,
The first day (Friday) is great for schmoozing. The systems are still settling in, and good listening is the exception as people re-evaluate and fine tune their setups. Toward the end of the day, you'll hear some good sound. Take advantage of this day to rub elbows with those manufacturers who's brains you've been wanting to pick.
Saturday is busy, but you can get a lot of good listening in.
On Sunday, everyone is burned out and anxious to break down their gear, but the gear is probably sounding its best this day. Hit your "gotta see again" rooms early on Sunday (before 1pm).
Cheers,
Thom @ Galiber