I think these devices will all work about the same so it's sort of a price game to me. You are setting your distance to a calibrated standard so you assume that the product is mechanically stable while it rattles around in your bag.
The red unit looks solid and is hopefully as rock solid as my RPP's mechanically. I like the price, the look and the simplicity. I also like the fact that Red always seems to take care of it's people when/if the next great thing comes along. If this is the "RPP" of flange focal length testing, count me in.
I am actually tired of "shoot outs" It's a tool, pick one. The SALT test was not really conclusive so a focus device "shoot out" is just more white noise.
Plus, Red has not let the entire cat out of the bag yet. They control the camera firmware remember.....