Where are you? Be careful of subs who recommend moisture products because those two products are not equal. In my opinion, they are at different levels.
Adam @ Synthetics is one of the best salesmen I've ever met. His sales software is amazing, he can track and follow up amazingly well - I could learn a lot from him. But I can tell you that I've passed on some major projects with Synthetics on the concrete. He has a broad spectrum of product. They aren't all the same. And as a flooring distributor I've had to really put the hammer down on subs who don't know the difference.
For me, Koester is the gold standard here in my part of California. When the entire floor comes up, and the hospital shuts down, and everyone lawyers up, and then the lawyers consultant up, the consultants always write the spec along the lines of:
Koester VAP 1 2000 or Ardex MC1 or Mapei EMB or equal.
"Or Equal" - a phrase I HATE in architecture. Nothing is really equal but I believe what you need to look at carefully is the Perm rating.
In my area the Koester rep is the expert. He's really been a beacon for me on doing things right or not at all. He continues to teach me a lot. When we have a problem I turn to him immediately.
I've never had a failure over properly done Koester.
And you don't have to take my word for it. Look at who's logo is on this document. They are the scientists for the Portland Cement Association and you do what they say period, the ultimate consultants. http://www.koesterusa.com/Testing/ASTM-E96-Results-for-VAP-I-2000-andVAP-I-2000FS.pdf