Some time ago when some of us were actively using Devil's Den Dave Santivanez of Ocala took some of us there for a quick tour.
Dave likes the facility. From what I remember, aside from the very clear water I didn't have the feeling that it would be good place for my large-long Type VII by32nd Parallel.
By not being good I mean not being able to navigate very well. There may well be places that I didn't see or don't remember.
I'd say very good for smaller boats.
Ginnie Springs is a private facility and there is an admission fee.
Hope that this helps.