They do warm up where skin to tpe come in contact and retain heat for quite some time. I found a bit of digits warms the pussy or anus or mouth fairly quickly.
As the water based lube begins to evaporate due to friction it gets tighter. You cant enter without lube. too much tight friction. I must say the doll i played with was high end tpe and tighter than half of the gals i have seen. if a gal knows how to do kegles then she is better than a doll. Also, I have had a few sp's that are starfish and almost as interactive as a doll. sad but true.
And to seven i say shop via Reallovesexdolls which is in florida which answers many questions via chat or phone call.
https://reallovesexdolls.com/ or pm me for more details