I found this 'Elastilon', and heard good reviews from website. Because lately we really feel trouble what is the best to install real solid hardwood floor over concrete, and got different opinion from different contractor, some saying - you can't install true solid hard wood over concrete, some saying - use glue with moistrue resistent, then sleeper, then plywood as subfloor and finally nail down...etc...
And now I knew this 'Elastilon', it is little pricy, but so easy, no smell, and I guess lot of contractor won't like you to know this product, otherwise they would lose their job..
So I am not sure people here knew this or not, just shared with everyone.