I think an MM pro would fill the gap between a 4s and 6s controller nicely, and guys wont mind paying a few $ extra for the higher voltage handling, and better heatsink and no USB port. Add to that an 8s MMM, and 12s BF-ESC, and Castle would be king of the... um, castle.
Neil... What are we going to do with you?
"I'm already pregnant, what other kinds of shenanigans could I possibly get into?" -A quote from the movie, "Juno"