NOTE: I answered this when thinking of dumbbell bench press.
Disclaimer*I do not have any scientific research to support this*
In my experience, it's been good. I've found when I pitch the day after doing a dumbbell bench i tend to throw harder than usual.
The bench press is considered a good exercise for pitchers; the dumbbell bench is basically the same thing but single sided. I don't see any reason to think its bad.