I saw Sarah today and she was pretty much everything the OP described without the headstand bbbj and all that. I would put her age in the early 30s. Natural small Cs/large Bs. Service is par with providers in the past. A little bit thin for my taste but if you like thinner girls then go for it.
F: 7/10
B: 7.5/10
S: 7/10
Repeat: No (I would say she is the standard for the agencies but nothing extraordinary)