Seconding John's review, this cage isn't quite a drop in replacement. I had to clearance a small nub of orange plastic directly behind the lower-front screw post. The cage didn't sit flush without it.
With the 41mm version, I also needed to clearance the white plastic directly above the top wheel (both sides), otherwise the wheel rubbed slightly. You could avoid that one with more crush; a 40mm version probably wouldn't need the minor Dremel action here, but definitely don't get 42-43.5mm versions. Maybe they work on the Rapid Red?
The cage was too short to flush mount with the stock barrel - about 5mm - but I had a parts-bin EAT with the same barrel (but longer) that I cut to size.
It was a little more work than I was expecting, but waiting anxiously for the final motors and Kepler wheels to put it all together!