Tom_M here. I don't understand all the negative comments about portable panels. If you want to park out in the sun and roast, fine but I prefer the shade on hot days. Also there are some places that I camp where I can't park in the sun so my only option is to set my panels out in a sunny spot.
I first mounted a panel to the side of my motorhome back in 2010 when I moved a 125 watt panel from my pickup camper.
This was shortly before heading to Florida. A bit on the cool side that day.

Later I added an 85 watt panel.

The 125 watt panel which weighs 27 pounds was a bit difficult to handle so I purchased a 180 watt flexible panel. I moved the 125 watt permanently to the roof. I built a frame for the flexible panel and it weighs 12 pounds.

I don't recommend using a flexible panel. It died this year so I replaced it with two 100 watt glass panels.