For sale: 5th wheels / west boylston, ma 2011 Keystone rv Cougar east coast 327res for years rv buyers have made Cougar #1 in its class. The reason? Cougar offers you more features, more innovative floorplans and higher quality, all at a popular price. With unique models like the Cougar den, your choice of several bunk house models and toyhauler options there's bound to be a Cougar that's perfect for you.