Difficult to clean, difficult to time. - Adams Arms P Series Micro Block Mid Length Piston Kit

I have both the Adam's (AA) and the Superlative Arms (SA) mid, adjustable, lo pro kits mounted. They both work well. I prefer the Superlative kits for these reasons: 1) The SA kit allows for the removal and cleaning of the op rod and spring without dismounting the gas block. With the AA kit, one must take off the gas block to remove / replace the op rod and spring. The AA gas block requires a hydraulic press to install or remove it, the SA kit can be obtained with a clamp on gas block. 2) The SA kit will allow the use of many more different free float rail systems. There is no dependence on what is a highly customized barrel nut as in the AA kit. The AA barrel nut places the rod "pass thru" at about every 20 degrees. Must use non-supplied shims, or gorilla the torque and risk distorting the barrel nut. 3) The AA kit's dependence on the use of the milspec barrel nut, or their proprietary barrel nut, forces the selection of the AA free float rail system as the only "affordable" option. AA lists others on their website, but most use a GI barrel nut, or cost a bunch of money. My AA rail had alignment issues, I sent it back. The AA system does have the op rod spring outside of the gas flow, and so is protected from it. The SA kit has the op rod spring in the high temp gas flow, so there's a question how many firing cycles it will withstand before needing replacement.