In my experience, B2B varies from masseuse to masseuse.
I've been to the place at Compton and the place on Worcester Street and at both places I've had women climb on top of you and rubs their tits all over you. They also lick and suck your nipples whilst grinding their pussies against you. I've generally been able to finger them and a couple of them have squirted. I got OWO off one girl.
On the flipside, I have also had B2B from ladies who do not allow touching or interact with you at all. They offer nothing more than a topless wank. The ladies in these places change regularly so I can't give a particular recommendation, suffice to say it tends to be very much luck of the draw.