In my previous house, which I was in for 20 years, I had nailed hardwood floors in the kitchen. There was absolutely no corrosion. And the flooring was much older than the 20 years I spent with it. I don't think they made nails better back in the day. Where would this moisture come from anyway?? How much water does this guy think you are going to spill and let stand? In my experience, very little water winds up on the floor. You have to me more careful of grit (I brought up four boys in that house- they tracked sand and dirt everywhere for over a decade.) I sense you are being up-sold here.

To get the water to HIT the nails, you MUST HAVE a breach in the polyurethane. And that breach must be EXACTLY over the nail head. And THEN you must have +++ moisture over time...

How many face nailed hardwoods have survived 60+ years (having multiple sand/refinishes using urethane/polyurethane) that have NEVER had the nails 'rust'? OODLES! Hundreds of thousands of these floors have never had a problem with nails rusting.

A POORLY cared for hardwood will always have issues. A properly cared for floor (face nailed or not) will continue to look beautiful AND be fully functional for longer than the life span of an average human being.

My money's on the 'up-sell'. And the Loba 2K Supra AT is fairly water resistant. Yes, 100 gallons of water sitting on the floor will eventually breach the polyurethane....but at that point you will have bigger issues on your hands than rusty nails causing dark black marks in your floor.

Thank-you both for the input. This helps a lot.