So far, so good
I've been pleased so far with these mats. I purchased 4 sets, which now take up about half of my 2-car garage. With the 4 sets, I have room for an elliptical, a spin bike, kettle bells and an abdominal machine. - with room to use them all simultaneously.
Having 4 sets, I was able to interlock them all together to make one large mat. There are ample connectors and corner pieces to make it all fit perfectly.
My only concern is the weight of these mats. They aren't cheap, but they aren't super heavy either. I suspect these will last me for a year or so, but time will tell.
For the price, I'm perfectly satisfied with the purchase.