We have both and leave the generator at home unless we know there will be a reason to use it. Since getting the solar two seasons ago, we haven't needed the generator so it stays at home.
Currently our solar is portable on 50 ft cables. That allows us the ability to have shade on the trailer and keep the panels not only in the sun but also tracking it for maximum power all day. It's not a small amount at over 700w but it allows for the use of anything in the trailer but the roof op air. That is covered with a small window AC.
Now even with all of that, if I were to go on the road I wouldn't leave the generator home. Solar is part of a balanced system and a back up means of charging is critical when Mr sun doesn't feel like playing for too long.
So before you buy or decide on anything, I'd like to suggest that you read up and get a general feel for solar, your needs and conditions to see if it's worth the effort. A generator is a must for most unless you get big solar or like us can cherry pick the best weather to camp in.