RE: Any one using JBA075A or dependable substitute?
As Turk says, the JBA .75 and .91 weigh the same. The .61, .75 & .91 are all built in the same case. The best one to buy is the largest, the JBA .91.
I have had an SK 90 and an Evo 100 on my US 60. The SK 90 requires a 15-6 prop so a longer gear or bigger wheels might be needed. I also have a couple of Tower .75s and they like a smaller prop. They really hum on an 11-8 or 12-6.
I would pick the JBA .91.