Lola is much better in terms of looks and services. I saw Sarah the other day but didn't enjoy my time with her. However, I have seen Lola three times so far and I have always had a great time with her.
Saw Lola and found her beautiful and service excellent. Clearly tastes vary judging by other comments! And as ever YMMV. Only answer is to try both- but given that Lola is leaving I'd try her first.