So be sure to limit your choices to only gals who have a history of solid reviews.

I live in a tropical tourist hot spot that's well known for its SW scene. That's not my thing though and I prefer online ads for my "window shopping," so I can get a sense of a girl's personality first.

Most of the time our local BP's /FemaleEscorts/ directory consists of ads from the same dozen or so girls, most of whom don't appeal to me either -- I'm kind of picky. Anyway, there are also visiting girls coming and going in a steady trickle of about 1-3 a month.

But on two occasions in the last three months I have seen a single-week flood of a bunch of new ads, most with pictures solidly in the too-good-to-be-true zone.

So here's what I wonder: Could these sudden spikes in new ads be LE setting up stings? I know the obvious answer is "yes it could be that," but how likely is that as a strategy?

That is some good advice, especially with all the stings going on all over the US.

IMO no reviews combined with "too good to be true" pics would be enough of a disincentive to keep me on the sidelines until they have recieved at least a review or two.

So many that it will takes me a few days to read the court records to see what is going on.

local new arrivals...  just starting out.  More likely they are touring providers, from outside the area...  or as you suggest, they are LE or scams of some type.  If they are touring, then the likely have reviews somewhere else.  As an experienced hobbiest, I'd expect you'd want to use TER's search feature to do a nationwide search on their phone.  Or you could contact them, from a private e-mail or hobby phone, and without saying anything incriminating, ask about reviews.  
You do need VIP to read the reviews...  mere presence of a review does not establish if it is a good review or a Rip Off warning.  TER VIP is not all that expensive for one month of service...  way cheaper than even one spoiled date...  
It's foolish to try to apply across the board generalizations to the hobby.
I guess the biggest red flag is the Too Good To Be True picts...  Is the rate also too low?  The combo is a red flag of something amiss.  
skb

one or two reviews would be enough for me, as long as they were by credible reviewers. One would actually be enough if was a reviewer I actually knew.

OTOH, if the only reviews were by unknowns, that would be a quite different story.

... I don't think so.   Its too easy to fake a few reviews.  Unless the provider has a has a history going back over significant time, certainly more than a month, there is nothing to say they aren't fakes by either LE or an agency.  

Once a woman has been listed and reviewed for a significant period of time, its pretty safe to assume she is who she says she is.  

Just my .02

Yes it is an election year and funding from the Feds to go after pimps.

On BP thing that look TGTBT usually are. It could be the same tired old local ladies trying to stir up some biz.

As the previous posters have said stick with well reviewed ladies from reviewers that have some cred.

In Los Angeles we had a rash of unattractive gals stealing photos of fab Brazilians, some who were TS, and publishing these photos and then trying to reap the rewards of misrepresentation. When you see something that is too good to be true, it probably is not true.
Research and see who has a track record of reviews that are favorable, keeping in mind that well reviewed escorts are constantly ripped off also. It is a tough call and an excited penis can send you in the wrong direction.
Use the boards on TER to check out with a 411 if the party is who they say they are, this is a good solution and available to all members, not just VIPs. You will find a cadre of friends to guide you and if no one knows who Milfy Milly is, then you probably do not want to know either.
Worse than a cop bust are the thugs, usually out near airports who will beat and rob you. That is reason enough to be careful. And as I always say, when you find a good gal don't move on; a good sex experience is hard to find so if it is good, stick around and enjoy it!

A few girls may travel together to share rooms, reduce expenses, so that could be the reason for the "flood." And real providers have been known to create multiple ads, different pictures, different personas (note: I said real, not good or trustworthy, though I did meet a lovely lady when out of town who had two characters she advertises, and lots of characters she plays with real passion and conviction - no, not that kind - so it is not always a bad thing).

It does not change the fact that you would want to find some evidence that they are legit, as it were.

Local or out of state phone numbers?

Just some thoughts for your screening. Info so far does not say LE sting to me, just proceed with care since it seems a little strange. Credible reviews and track records are best, of course.