My boy lives happily in a 41 quart. As for differences. If you aren't breeding I'd get a male because for the most part you'll be able to buy cooler genes for less money if you get a male as female are more valuable in the eyes of breeders.
Personally I don't find ball pythons to be the best for beginners as they can be very picky about both their set up and their eating. I would consider a ball python and a BRB about the same level of 'difficulty'. Both snakes really need to have their husbandry perfect to be happy and even then a ball python will often go on a food strike that can be very stressful for a first time owner.
I consider cornsnakes the 'go to' beginner snake.![]()
Not saying that beginners can't own ball pythons or BRB, you just need to make sure everything is set up right.
EDIT: also an older more established snake is going to be easier than a hatchling. A hatchling of either species is not going to be happy starting out in a 41 quart, way too much room for them to feel comfortable.