In February of this year I bought one of the 3.6" S&W CSX E-Series pistols.
Since late 2015 I have been availing myself of the advantages of Trijicon RMRs.
Since Trijicon doesn't make anything with a footprint compatible with the CSX my choice of Red Dots was narrowed down.
I'm a "made in the USA" guy and the SIG Romeo-X is as close as I could get.
I prefer the 6 MOA for defensive pistols, though I do have a Trijicon 3.25 MOA on one of my S&W M&P9 PC Ported pistols.
The Sig Romeo has a built in rear sight which is a nice feature as the rear sight must be removed on the CSX to install a Red Dot.
As a matter of practice I polish the feed ramp on all of my new (or new to me) pistols.
Ten yards sighting in the RMR with 124 FMJ PPU.
Flyer my bad.
Out to 12 yards with my preferred carry ammo.
I haven't found a holster I really like yet but this 1791 for a SIG 365XL works for now.
So far I've put about 500 rounds through it an everything ran flawlessly, including cast bullet reloads, FMJ, and of course Federal HST.
After all that shooting the little CSX needed a good cleaning and as a long time RMR user I practice safe cleaning.
I'm very satisfied with the CSX and the SIG Romeo-X
Cheers
James