LOVE this stylish Design Studio Expandable Dog Gate.  We have two that we use.  They are easy to use and do not leave any marks on the walls.  Our dogs have not challenged them and even our kitty has not jumped over them.  They have a nice wood look that matches the interior.  These are nice for the laundry room area that opens to the back yard, so that they can go back and forth as they choose.

Pros: Easy assembly, easy to use, good price and nice finish
Cons: None