more facilities in the US are trying this model. best examples:
Body Empower - Melrose, MA - LM only
Group X Factor - Foxboro, MA - LM only
Bodyworks - Lawrence, MA - LM & Free-style
All are facilities offering just GF (Bodyworks might offer other programming types throughout day - freestyle options - may have dance classes etc)
Consider your target audience; potential instructor base; marketing plan/$ to make it all happen. if those 3 are in place, you can really consider doing it & being successful. would suggest you connect w/ your local LM agency - LM Mid Atlantic, talk to Erin there, and toss ideas past her for some advice. they can give you info on other facilities in Mid Atlantic area doing Studio based facilities
good luck!
B