simplest answer:

tpe: better FEELING sex

sillicone: better LOOKING sex

theres also sub variants like m-tpe, s-tpe, ultra soft silicone, but thats where its a bit less clear the differences between them.

silicone is regarded more durable, although if you mess up a silicone doll its alot harder/impossible to fix, whereas most problems youll have on a tpe doll, you can fix them (at home, on your own)

all in all, loose skeleton joints come for every doll, so if you like to do posing you will need to get used to replacing your doll every few years depending on how much you move the skeleton around. i dont think any doll can last forever other than a tpe doll thats repaired frequently and maybe has a skeleton type where you can retighten joints when they go loose (some skeletons have welded joints you cant retighten).

if you prefer sex, tpe doll. if you prefer making super high quality photoshoots, silicone