Joe Bob Outfitters Matrix Arms will not fit any type of Piston system as far as I can tell. SA is definitely NO GO. Not even close
Seekins NOS will fit over the SA .75" clamp on, but it is touching on bottom near the screws and on top at one side or the other of the piston. It fits, but your handguard will definitely be influencing your point of impact.
BCM fits, but only barely. I had to take my rail and gas block off and back on 5 times before everything lined up. I have the .75" clamp on. I had to sand the screw heads on the clamp. Then on top you only have a few thousands to spare between the piston and the sides of the top of the rail. However, the BCM is so rigid you only need a few thousandths and it will never touch. The set screw model would be an easy install as long as you get everything straight. BCM is good on the SA IMHO.
Obviously, Samson Evolution fits no problem and Seekins MCSR whatever clears by a mile. Anything using the BAR nut or the enhanced uppers should fit easy.
I have SLR's, but have not tried them. Pictures above show they wont work.
A friend has an Odin Works O2 rail on an SLR set up. I have not tried it, but eyeballing it next to the SA kit it looks like it should fit. I have not measured the width of the upper channel. The O2 is one wickid looking design.