No different than most masseuses and they're not always consistent with the same client.
Agreed.
Often the SP's who masquerade as FBSM have a list of punters who she is very happy to fuck anytime, then sometimes and then those she wouldn't fancy in a million years.
IMO, these SP's feel safer working within a so called legit shop rather than in many cases a grubby room or flat. I know a couple of "legit" shops where some SP's just offer a HJ under real pressure whereas others can't wait for regulars to fuck them.
For obvious reasons many of these SP's are not reviewed by punters which is a shame. Given the circumstances I normally add additional information via PM to established members but this has risk.