Re: ESP Arming Adjuster and RG2550EGK
The ESP Arming Adjuster works fine with the OFR/EDGE/LO-PRO/Edge pro. Got one installed in all my guitars, and I have one on all four types of bridges. All of them work fine. Seeing that I did that review of that ESP Arming Adjuster here and probably the only one that has the arming adjuster installed in guitars with all four of the prominent trems, I'm pretty sure that I can guarantee you that it'll work fine.
(Some routing needed to be done on my guitars but I've installed the arming adjuster for others who didn't want to get thier cavities routed. It just had to be installed a little further out)