I see the 7274-x has 4 different models. I only difference I can tell from the documentation is that one model has a longer pull handle. What am I missing here?
Probably not much..... I would suspect they had a OEM they where needing to service that had slightly different needs.
Before you commit to spending $75 on a circuit breaker, search the forum for discussions on the merits vs fuses. I have one breaker for the Alt. Field.
Nothing else in my panel needs a disconnect that is not handled by a switch backed up with a fuse.
The difference between the "aviation" and the "commercial" product is in the MilSpec designation. Again, to hazard a guess, they throw them on the test bench and those that meet the MS get that designation. Those that don't become commercial. Just a guess. Bimetalic switches have inherently wide tolerances, one between the next.
I can not think of any reason to use the aviation version other than to say you have a MS breaker. Reading the specs, they are both going to do the same job, which is "gross" protection of the wire in the circuit in our simple electrical systems. However, they are the same price, so, go figure.....
Stein carries several well known brands, for much less. So, if your sold on breakers, and not stuck on Made in America, you can save some $.