I've seen three TS porn stars that I can recall. None of them were significantly better sexually than vetted BP gurls. Note that I did not pay what I would consider "porn star" fees - they were in the 200 range.
I have yet to experience a TS or GG who was worth 500, strictly from a physical performance perspective. If seeing a low volume provider is important to you, then it might be worth it, but they generally are not going to physically please you any more than providers here or on BP. My two cents