They're only two major battery manufactures around now. Johnson controls is the biggest one. They make Walmart, AutoZone/Advance, Interstate. Pretty much all of them are just relabeled and different grades of Johnson. I believe Exide is the other major maker of US batteries....
AGM batteries are really the best right now. They are so much better then a flooded cell battery and last much longer, they can take more abuse and hold more power. An AGM will be very unlikely to leak if that is a concern of yours.
Optimas are great and I have had a few over the years but IMO not worth the premium price anymore..... unless you want their cool look.
96 Cougar Sport
96 Tbird LX