Dennis,
Check the weights of the interstate 6V batteries at Costcos, I think you will find that they are within a pound of the Trojans, and if so, they are literally the same capacity. There are no versions of golf cart batteries that are half the capacity of others, that I have ever seen, given the application demands a lot of deep cycle reserve capacity to run the golf cart.
On the Trojan front they are excellent batteries and I was able to buy blemish ones from a large golf cart dealer at a reduced price so that is what I have. I would not pay a lot more for a Trojan thinking that I am getting a lot of extra capacity, if the weights were within a couple of pounds.
Later Ed