I saw this at a big box store this week and wondered how good it is and if you've used it?

I've never put any cement board or such under tile countertops and have never had a problem just putting the tile on plywood.

Any thoughts about this????

THANKS

Saw WHAT?

Easy Mat Underlayment (the heading for my post)...that's the name of it. It comes in a roll 48"X10' and kinda looks like rolled up cement particles.

All that is, is a bond breaker material. Its used to prevent the movement from the underlayment to the tile thus preventing the tile from cracking when the underlayment swells and shrinks from moisture. It does have a purpose but not sure if this should be used in this application.
This type of material is used when the floor system already has sufficent strength and does not flex. Its not a replacement for cement board if the floor experiances any movement. It to will flex.

You should never tile over just the 3/4" plywood, you need to add a 1/4' cement board and GLUE (with thin set) and screw it to the plywood prior to the start of setting the tile.