Solar can be a very good thing but you need to do your homework so you don't get disappointed. We would need the specs on the system CW is offering to give an opinion like type/model of controller and the type/wattage of the panels to see if it's a good system or they're blowing smoke.
Nobody can tell you the panels will charge something in 4 hrs as there are too many variables.
I went with a Honda EU2000 10 years ago before solar was mainstream like it is now. But I've looked at solar from every angle and can't justify it for my type of camping. If my use changes, that decision could change.