It is definitely worth playing with.
I find my 400mA 6W panel is big enough to
work as a maintenance charger.
I also have a 1.2A 18W panel that can keep
up with our live aboard house loads in the summer.
On a very sunny day it can be powerful enough to
cook a battery if used without a charge controller
and not watched carefully.
Islander 30 II 'COOL'