Dondo, if the lady is brand spanking new to the endeavor and so green she pisses grass, and she immediately elects a no review policy, then yes, I would agree that would be a red flag . . .
In the instance of the lady being well established and respected within the community and her receiving continuous compliments in open and private forums, her electing a no review policy is probably of little consequence to her business most likely and frankly, she probably doesn't want the type of attention that an abundance of reviews can occasionally bring.
Keep in mind that a no review policy does not insulate anyone from a valid alert or from general discussion about their service, if it be sub-par or spectacular (especially in the men's lounge [so I am told]). It (the no review policy) only eliminates the formal review form from being used in the review section.
For the Escort or provider making the election of the no review policy, it has great consequences. She can not have an active Showcase and she cannot advertise in the threads specifically set aside for such notifications, so she most likely is very secure and confident in her performance and abilities, and secure also in her client base (or her ability to obtain new clients) to even consider to elect such a policy - further, she might be in a position to have to decline new clients or is simply so low volume that she doesn't want them . . . many ladies will only see one, two or three gentlemen a month as they may have a "day job" or significant other, etc. . . In any case, a no review policy says nothing about the legitimacy of a verified provider or their performance and in some cases it may infer that the lady in question is consistently a best choice.
I agree with bigryan, that this is a case where the initial logic does you a disservice - it isn't poor logic, but you aren't weighing all of the factors in your decision making. As such, you may be missing some of the better opportunities that you may have available to you, but you'll continuously miss them if you base your decision from a standpoint of whether or not the lady is reviewed - and continue to place such a strong emphasis on that factor . . .
As a real life for instance; when Plaza Escorts was active, ALL of their ladies were subject to a no review policy - however, it would be argued by MANY a gentleman here that at times, the best ladies available in the city were available solely - and exclusively - through Plaza . . . Many of whom went on to become some of Kansas City's best independent Escorts and providers, with stellar reviews here on ECCIE (and some without reviews - LOL) - ladies such as myself, Lori, Bristol, Alexxxis - and many more . . . and none of us were ever reviewed while we were exclusively contracted with Plaza Escorts, and none of us suffered from a lack of clients.
Good luck in your search.
Kisses,
- Jackie