I may be missing something, it seems like the majority of people in here don't really mind if these aren't available. They have one of the highest power ratings for their size and weight (higher max power than either the Bag OR the MiniCIM, and higher than any of the AndyMark 9015s), at least according to
the specs I gathered. I have been a little hesitant to use them for high torque applications if stalling was going to be standard, but they are one of two or three small form factor motors legal in FRC.
We got into a situation this year where it appeared that the simplest way to increase performance of our elevator was to replace a Bag with a 550 because the size was similar. I guess that won't be an option anymore.