Scott, I agree natty crotch can be used in many scenarios, but there are those "specialties" that require a little something extra. I'm interested in it because I run into some trees in some tight areas where the control up top is highly advantageous, and a natty crotch scenario really doesn't exist. It's the same with the AFB. I've only pulled it out 3x, used it on only two of those scenarios, but so glad I had it when I needed it. I used the MB 2x, and it worked well in those scenarios, so it fits that mode I'm looking for.
Other than playing with it to get familiar with its workings, I've used my MB only a handful of times, but I like the option when in a sketchy tree where I want to control the descent of the piece rather than the groundie.