I work in a Costco tire shop and Yes all our batteries are made by Johnson Controls!! They are great batteries and we get more returns of the optima's then the kirkland ones. We usually cant keep most of the batteries on the shelf and sell out quite often so I do recommend calling first to make sure we have them in stock
Oh and a common miss conception is that optima batteries ARE NOT gel cell batteries! They are an Absorbent Glass-Mat Separator (AGMS)
There are only two major amican battery manufacturers. JCI is by far the largest. Specifications vary from brand to beand but by in large... unless you are buying a cheap asian battery, batteries with the same rating are likely to be nearly identical so buy based on price and warranty.