I've been thinking about this thread since it started, and I'd like to reply. I also wondered about the 24/60 case, with only 1 motor for it. I told myself if there were more choices for it, I'd buy a couple.
There is another thread here, about these motors in the Aerotech open thread. When I saw that they were working on other motors for it, I bought 2 of the casing sets, and some reloads for it. I figured that when the other loads were certified, it might be a problem to get the hardware. I also noticed that the current F35 reload is very close in overall performance to the F37 reload for the 29/60 case. An adapter takes care of the size difference, and the F35 is about 1/2 the cost of the F37, if you buy these from Wildman Rocketry. (Tim has very good prices on these).
Now, just recently, another load was certified for this case, the F51NT. Supposedly, the others will follow soon. So, I am eagerly anticipating the new motors for this, but I assume it will be a month or so before we see any of these new motors.
Phil L.