It would seem that when Monaco took over building Beavers, they switched to a cheaper wiper arm. The lower quality arm was and is a poor performer when the chips are down, like snow, sleet, and high wind. Beaver Coach Sales replaced mine with "boomerang" style blades built by a quality company, and though they are strange looking when pulled away from the windshield at cleaning time, they do conform to it better when in place. Boomerangs are relatively simple; radial arms will do (as long as it's higher quality than Monaco's), and there is no complex multi-sprung blade frame.
Like any other, if a bug or other dirt dries hard on the blade, there can be streaking and missed spots on the glass the next time the wipers are used, but that's the only time they don't thoroughly clear the windshield. My only issue with them is that BCS used an arm/blade combo that doesn't cover as much of the windshield. That fact I was warned of ahead of time by BCS. Apparently where the blades mount on the arm takes a longer blade beyond the passenger side extreme curve - it's a matter of proper configuration. The smaller swipe zone took some getting used to, but it is certainly enough to safely see, and the more thorough job where it does swipe is an big advantage over the OEM's. The curved shape presses more evenly to the glass and conforms to curves. Mine have been known to completely remove bug splatter in a couple swipes, as long as fluid is squirted and the bug hasn't been baked on for several days.
Don't wait for a blizzard to tear off your wimpy post-SMC OEM's like I did; believe me you don't want to go there. Even if you have pre-Monaco wipers, you should consider retrofitting with boomerangs, though they aren't cheap (what quality part is?). The quality AM brand arm I think is limited to 28", though TRU Vision boomerang blades come larger. Arms are about $40, blades $45-$49.
I've used Rain-X in the past also, and it does work, but the windshield has to be immaculately clean, there's time involved to put 2 coats on a large windshield, and it has to be done regularly. In Canada at an auto parts store I got a nano-technology product that coats the windshield filling in microholes that bugs and dirt stick in, and it works well also; though more permanent than Rain-X, AquaPel or similar silicate products, it is spendier and a motorhome windshield requires 2 packages of it to cover all the glass.
http://www.youtube.com/watch?v=_uBep6PERt0Joel
