I have a 2010 28 foot Fleetwood Class C. It sat for a number of years, and the past couple years I've fixed it up and have been using it. It drove pretty well except the steering seemed a little bit squirrelly, and it overreacted to seams on the freeway. I wemt under and looked at the OEM stabilizer, and it had pits on the rod from corrosion. I took it off and found that it was completely shot.
So I ignored all the hype about the expensive self-centering steering stabilizers, and ordered $30 Monroe stabilizer, that fit on perfectly. I also put a boot on it to try to protect the rod.
It drives beautifully now. I could drive one handed if I wanted to but I normally keep two on the wheel. Now when I go over those road seams the wheel doesn't shake it all. Honestly, I just feel like I'm driving my pickup truck when I'm driving the motorhome. It has 196 inch wheelbase, and I think that makes a huge difference.
By the way it did have one other issue... the bracket that the stabilizer mounts to on the passenger side was loose. I could not torque the bolts up to spec, and found that they were stripping. So I tapped them up to the next size and put new bolts in, and have them torqued up to spec now.
I personally don't see a need to upgrade the stock sway bars. I've driven it in pretty strong side winds, and it's controllable. And if it gets too windy, I just pull over and wait it out.
But as others said, just drive it and see what you think.