I have an 18' awning on my Cougar. I got my idea from seeing the Awning Pro video on their website last fall.
2 weeks ago I went to Lowes and bought 2 10' lengths of 4" thin wall sewer pipe. I split it lengthwise using a Skilsaw with a fine tooth blade installed backwards (it makes a smoother cut) and also cut off the bell ends. I laid it on the garage floor and kept it from rolling around with some 70lb sand bags. It was difficult to cut it exactly straight, if I were to do it again I would cut it in 5' lengths first so it would be easier to handle. It wanted to roll from the vibration of the saw. I would also do it outside instead of in the garage, the plastic dust makes a mess.
After splitting it lengthwise, the pipe wants to curl in on itself overlapping where the cut was made about and 1 1/2" or so. So I just cut off the overlapping part using the original cut as a guide. This left a gap of about 1/2" or so similar to the Awning Pro stuff.
It was too hard to handle and slip on the awning as a 10' length so I cut them down into 5' sections as seen in the video (I think the Awning Pro stuff might be in 4' sections maybe). Then it slipped on great, overlapping each section a few inches, I pushed each end against the awning arms, hoping this may keep water from getting inside the rolled up portion of the awning.
With it installed on my camper it looks just like it does in the video. I should have done this last fall when I first got the idea.
I live in the Midwest and don't travel too far from home, so I think it will hold up under the sun here. And considerable savings over the Awning Pro stuff.
If I had seen the photos of the vinyl gutter I would probably have considered doing that instead possibly, looks like it might be easy to install on a shorter awning than mine though. Just saw that today.
I owned my last camper 12 years, stored outdoors. The awning started to rot through along the mounting rail after about 9-10 years, and kept getting worse of course. It got to where you needed an umbrella even if you were under the awning. I patched it with duct tape on one trip, the tape blew off on the way home but it worked for the weekend.