In our experience, our 490 watts of solar panels on our fifth wheel produce 100-160 amp-hours per day, depending on how depleted the batteries are in the morning, how much we consume as the batteries are charging during the day, and how sunny it is.
We did tests on our sailboat (which has 555 watts of panels) where shading is a big issue, and we found out that having the panels shaded was a lot more detrimental than having them pointing away from the sun while the boat was heeling.
As shade from clouds move across the panels, we often see the charging rate drop to about two-thirds -- say from 24 amps to 16 -- and then it rises again as the sky clears.
In general, more is better. If I were to outfit a new RV today, I would put at least 750 watts on the roof. There's plenty of room on our roof to do that.
Panels are half what they cost when we outfitted ours 5 years ago. Plus our lifestyles have changed and we now run two laptops for many hours each day, whereas when we first outfitted our trailer we used only one for just a few hours a day.
We reported our various shading tests on these two pages:
Solar panel installation on a fifth wheelSolar panel installation on a sailboat
