I have a knock off brand sold on ebay and amazon.. I love it, very light and easy to take with me wherever I go. I love that it has a built in bottom, keeps my baby from accidents on carpet, food spills, digging, messy treats.. all confined and easy to wipe up.
I got the medium one as the small one just seemed to small for a really good play area, I use it for play time chasing toys and balls...
Amazon
Mine was much cheaper than the pet gear one was, however I've seen that one at the petstore and would say the quality is similar, the pet gear one uses a canvas like material where as mine is more like a rubbery plastic backed ripstop tent of material, both I think would hold up as long as they don't chew on it.. I sprayed bitter yuck stuff on the zippers where my puppy wanted to chew on it.. she hasn't tried since.