Nothing against the keepers, but side movements, especially on the SXR make them pop up and over the plates. Some nose stabs do also, tail landings they are great. I tried developing a new kind, 1/2" thick but they limited travel too much. Best I have found is to add 1/16" washers under the keepers. I have one set of modified ones, but they are grind to fit. You can see where I added more in front of the tab. I added more AL to stop the motor from forward jumping. Then I gave up and just rode the thing!