I have the standard Sherpa carrier. My dog is of similar size as yours. Does he love it? Nope. Does it work? Yep. He's traveled with me dozens of times on several different airlines. The benefit of this carrier is that I know it's airline legal. I've never been questioned about the carrier or the size of my dog by any flight attendants, gate agents or ticket agents. Regardless of the carrier, my dog isn't going to be all that comfortable during a flight.