I prefer to cover my entire RV. It sits for several months without moving during the winter, so why not protect it the best you can? You can drive through the storage yard I'm in, and it is pretty easy to tell which units get covered, and which ones don't. With the full cover, I can leave my roof vents open while it is in bed for the winter.
Becky, Bob and Taylie & Bode
2009 Silverado 2500HD Duramax/Allison
2014 Heartland Sundance XLT 245RL