floor mounted? got any pictures of that kyou can share?
as for kyour sons scope planets are the go. once a decent planet comes around he should see plent of detail on it

. the moon will also look great in it too! besides that there are plenty of nebula and globular clusters he should be able to see (in particular the bright ones). if you can get to dark skies he will see even more

dont expect views that you see in pictures tho as thats just not achievable with human eyes.
the 10" floor mount has me insterested tho....
welcome abaord