I'll recommend the cover I'm using and documented in this thread: http://www.hilotrailerforum.com/f32/...er-cover-5677/
It's made of Sunbrella, which is the ONLY fabric you should think of using in a sunny area like NM and AZ. Mine looks brand new and is excellent protection for the trailer.
Hi-Lo 1707T - Tire Minder TPMS on Tow Vehicle and Trailer, 300W Solar Battery Charger, Equal-i-zer WDH, Progressive Dynamics Converter, Fan-Tastic Fan
2014 F150 Platinum 4x4 3.5L EcoBoost SCrew