One bad review is not enough to ruin a provider's business. You have to take the whole set of reviews in context. Having said that, it doesn't mean 100% positive reviews means you will have a great date either. She may be well-reviewed with all 8,9 10 scores, but you might just not click. Then again, she may have a 6 score but you hit it off.
To be honest, when I read a review, there are 3 things I'm really interested in: a) description of her looks-- does it come close to her pics b) price-- can I afford her and does her price match what her ad says c) menu-- is MSOG available ( a must for me) and is BBBJ available (may end up being a deal breaker based on other factors).