Hello, first post here. I'm planning on glueing engineered flooring onto a concrete slab. Originally I was going to use Mapei Planiseal WFM then the 980 to glue down the wood. I've heard the Mapei adhesive and sealer are much better to work with, but a guy on Craigslist is unloading a lot of the Bostik MVP pretty cheap. I can get it for at least 40% less than what Lumber Liquidators wants for it. Has anyone tried using the 980 on top of the WFM? Thanks much in advance.

Last year I got the go ahead on a job that another company was kicked off of. The slab was already sealed with Planniseal , and I had a pallet of Bostik's Best in stock. Needless to say I wanted to use the stock. I talked to Bostik's technical dept. Basically they told me there shouldnt be a problem, but they wouldnt guarantee it. That was all I needed to hear, and used Mapei 990.
So it's a judgement call. I couldnt chance it with a client. But in my own home I may have used the Bostiks Best. But is it worth the $ difference for peace of mind ?

Call the man and get it in writing. Course, if anything goes wrong you know what their answer will be.

How old is the stock? Could be out dated.

There's really nothing he can get in writing.
Bostik will not guarantee their adhesives over another manufacturers vapor barrier.

Yes, it will work just fine.

They both have the same exact properties and chemical makeup.

I have used Taylor's 2071, over WFM with outstanding results.

I would not hesitate to use a moisture cure urethane adhesive, over WFM, or MVP.