The dealer included "Carefree of Colorado" slide awnings with our 2008 BC 3300rl, so I don't know what the cost is. I have no complaints about the operation, but they do flap in the wind, which I assume any brand will do if the wind is strong enough.
We are full timers, so, when we are going to be parked in one place for awhile, I insert blow up air mattreses (27" X 72") between the slides & the awnings to quiet the flapping. It works fairly well, but sometimes in a strong wind they will come out.
The best mattress to use can be found for $2.00 at the Dollar store.
We recently took a month long trip from Texas to Ohio through AR,TN,&KY. There wasn't any wind problem & it sure was nice to not worry about debris on the slides.