IMO, commercially swaged balls from the big boys like Hornady and Speer are awfully hard to beat for quality, what with swaged balls supposedly not having any voids/cavities in them that can occur when casting a lead ball...pretty darn uniform sizes and weights, etc...and they're usually priced accordingly for that quality.
On the other hand, commercially cast balls from a good quality source can also be very good, and are less expensive...one excellent source being Eddie May's Cast balls in Georgia.
Casting your own might be even less expensive in the long run, but has it's own related demands and issues like many 'reloading' type hobbies.
I've begun using more and more cast balls from Eddie May for weekend shooting but always hunt with Hornady...not saying Eddie May's cast balls aren't good enough to hunt with, it's just that I've accumulated a lot of Hornady's over the years at close out prices, etc.