I'm in the process of scheduling my visit with a provider who has zero TER reviews. However she is well reviewed on another site. Is this a big no-no? Is TER the holy grail of reviews? One of the reasons she may not have reviews here is that the city isn't even listed as an option under the search function and doesn't have a regional board. (Yes I've looked for her phone number and it doesn't return any reviews).

It's like news channels.  Do you trust Fox over MSNBC or vice versa?  There are other good review sites, much like this one.  Each has it's own strengths and weaknesses.  I prefer to see ladies who are reviewed on multiple places.  That way it gives you a good idea of consistency.  That's just my personal preference.

Although TER is not perfect (and really, what is perfect?), I do generally trust with a grain of salt what I see and read on here.  I also talk to the ladies and clients myself to get a better handle on what I'm going into prior to a visit.  

I know this advice seems vague, but use your best judgement.  If you have to question yourself too much then that might be serving as a good warning to you.

She may not be here because she has been banned or delisted here for any number of reasons, or it could be that she just hasn't received her first review here.

I have seen ladies that aren't listed here based solely on the recommendation from someone I trust.

TER is not the "holy Grail", it is one reference.  If you have reliable information from a different reference, go for it!

but what is right is TER is supported by guys.  The funding comes from us guys.
Look hard at other sites...  some have reviews but are provider driven.  I know some locally who have glowing reviews on a provider driven site but TER reviews are very low.  Follow the money.  Now not all are like that.  I know some reputable providers who are TER reviewed as well as the e site & quality always shows.
Does the provider have a web site?  I have found a site represents a commitment to professionalism.  
Best wishes,
skb

Keep in mind, some girls dont want to be on TER. That is their choice. I know one lady who had 2 pages of reviews all giving her 9 and 10 for looks and 9 and 10 for performance, than she asked TER to remove her reviews for personal reasons.

Some providers think TER allows too much visuals in the reviews and they are above some of those visuals and thus do not want to be on TER.

I think this happens more often than we know.  These are good or even great ladies but due to relationships, legal issues surrounding divorce & child custody, the provider correctly needs a low profile or even stops or pauses her business activities.  
Some ladies wish to remain UTR (Under The Radar) as a business plan.  

This is not for us to say.  I respect the lady's right to run her business...  and her life...  as she sees fit.
skb

There are plenty of awesome providers who have many great reviews on other sites that arent here on TER. I know many ladies that choose to NOT be reviewed on TER, but allow reviews on other sites!

Have fun sweetie!