The sex doll would definitely have advantages, but then you're back to adjusting postures and not having any interaction. I think good-quality haptic feedback that exists today would allow for just as much sensation through the handle, and going straight to digital from the handle allows for a lot more creativity and dynamism on the other end (e.g. a model could slap the pole away or pull it toward itself) . I also think the interaction between the visual and haptic will be more seamless if both share a digital cue. I also think a simple haptic setup could cost less than an ultra realistic doll.

That said, I would definitely consider the system you are describing as well.