If your primary goal is the snake feeling secure (which it should be) then a tub is a much better choice IMO. Glass tanks seem to stress a ball python out due to complete exposure on at least one side and husbandry requirements are more difficult to meet than in a tub in my experience.

I know many people want to have awesome looking glass set-ups that are fun to look at and show off to people, I just feel like ball pythons aren't the best choice for a "display" animal.