I messed around with the big basketball before - it's weird and fun but didn't do any drills with it or anything.
With medicine balls we used for post move drills. I think they worked well because it taught you go up with power. Carries over to game play pretty well. When I was a freshman in HS and we started doing those that shit would wear my arms out pretty quickly. By the time HS was over we did it for like 20 minutes at a time
I played at a D-1 school some years ago. I never used to BIG ball or the heavy ball.
One of the walk-ons used a big ball to help him shoot; the guy had a jumper that JJ Redick would envy, but he was like 5-9 and slow. He couldn't get it off in a game, but he could flat out shoot in practice.
Not much of help either way. Naturally a medicine ball would be of more value. Plus you can use it for training your abs............On a side not the vert shoes actually helped, if you can make it past the first couple of weeks with them...I only play like one night a week now though, mostly just officiate.
I used it Sr year and in jr college. We'd do drills where coach passes the ball to us under the basket and you'd have to do a quick turn around and dunk it. It's a good drill for post players.
I've also worked at nba basketball camps for kids and it seemed like they had a lot of big balls and medicine balls, so I'm assuming they're there for a reason.
It did wonders for my conditioning I'll tell you that much. Burns your shoulders like a motherfucker.