>>6880308I'm sure they can add or remove scars and surface details, but I still doubt it's a completely new, from-scratch sculpt each time. There must be a master model they use as a base.
On a related note, I should've also mentioned that I flipped the image of the SC Rex in my comparison since I couldn't find a profile shot from the same side. So the leg positions are in fact identical across all Rexes. Forgot I did that and tricked myself, lel.
Regarding the TnT, I didn't realize its joints were actually tight. My mistake. Impressive work on Mattel's part. This only confirms that you'll have an easier time creating that naturalistic droop across the whole figure with the TnT. The EC has the neck and the SC has none, so you're stuck with the sculpted erect pose there.
Having that said, the TnT is reportedly more difficult to balance on its feet, so if the torso and head are bowing down, you may need a counterweight on the tail. Dunno if I'm feeling that button under the foot for the same reason.
I'm personally shooting for the EC when the Legacy Collection comes out. Seems to have the best of all worlds, with a less contrasted (compared to the TnT) but serviceable paint app.