I too have a BETA 57, and was wondering if instead of using it on the snare use it on the toms, and then buy a regular 57 for the snare.
This would be my total setup:
-SM57/snare
-AKG D112/kick
-BETA SM57/Between the floor tom and 14" tom
-SM94-LC/overhead (maybe another one to do X-Y later on)