Evan metered the RSTA on my 16" LMT and POI tested the production RSTA today on his APA Genesis.
Un-suppressed with the 2 port brake he shot a 3 rounds of Lake City M118LR in 1/8MOA. His suppressed group was 1/4MOA and shifted 3/4 MOA down. He said it's hard to hold in 1/8MOA (which is obvious) so he honestly doesn't know if the can or he is the issue with that 1/8MOA that got away.
On the meter the LMT 16" CL with brake mount was over 170DB. With the can on FRP was 142 and the 10 round average was 138.3 for a 31.7DB sound reduction.
I looked around and found another source on the internet putting un-suppressed 16" .308 at 169.9DB so realistically that probably is right in there, even though the brake obviously pushes un-suppressed artificially into the mid 170's.