as a person working in RV sales, I can understand why many (if not most) dealers don't like to order slide awnings on their lot models .... as a person who camps (we've towed ours just under 40,000 miles in the last 2 1/2 years), I wouldn't want a camper without them ... our current camper has 2 slides with awnings and the 3 slide model we are having built will have awnings on all three slides .... my own personal preference is for A&E's:
http://www.campingworld.com/browse/skus/index.cfm?skunum=20393d&src=SRQB
I like the way their jointed vinyl encloses the awning roller when it is closed ... the only problems we have had with our slide awning is fraying of the leading edge of the frabic where it extended from the side of the camper and goes over the roller, I believe this vinyl covering will correct that problem ... we have found it simple and effective when camped to simply run the slides in and out following a rain (as noted in another post, stand back when doings so)
Jim