Gizmo is scared to death of the vacuum cleaner and the other day, he almost made it over the side of the playpen. Scared me too death and I figure its only a matter of time even though he is only 3 months old and a mere 2lb 4ozs, but I was worried enough to get a better playpen :-)
This is the one I bought
Amazon.com: Richell Expandable Pet Pen Medium... , because it also has a matching top that you can buy seperate, which I did lol, so they cannot climb over the top. I also liked it had a door near the sleeping area to let them out, as well as a slide up door at the other end for changing potty pads easily, plus it had enough room for all his food, water nd toys so he can play. I will let you know how it works once I get it. I can't wait !!!!! It had the added bonus of being almost the same color wood frame as my hardwood floors :-) it looks more like dog furniture than a playpen.