After a few months of trying this bed with 3 different high end mattresses, thinking the mattresses had issues and way too "watery" (too much motion transfer), it turns out it's the poor construction. I bought a new bed of the same type, slat bed, and the very same mattress works great on it. 

And now after just a few months the middle bar legs of this bed frame is already bent. 

It may look reasonable but it's not a quality bed. Even if you don't mind the motion transfer introduced, it probably won't last more than a year.