The Bureau went from the Aimpoint H2/T2 to the SIG in 2016/17 due to cost.
At the time SIG did not have their facility in Oregon and played purchase rule games with “assembled in USA” by essentially having a Chinese maker, build the Romo for M as parts kits, which were then imported and assembled by a US electronics company in California. There were some initial problems with the mounts and mount screws supplied with the early Romo 4M. The Romo 4M worked well when it worked. However, some of them would seemingly die at random. The circle dot reticle was particularly popular with those who had used EoTechs.
For this latest round of testing. Submitted the duty and the Comp M4S, both of which passed and received contracts.
My understanding is the Trijicon RMR HD and MRO were also approved as carbine optics. Not sure if either will get a contract. I’m also not sure how the MRO passed given its history of parallax issues.
If they continue to follow past practice, the aim points will be added to guns as they are built or rebuilt. Existing H1/T1, H2/T2, and SIG optics will continue in service along side the new optics for some time.
My agency has been issuing the Romo for as a carbon optic for a couple years now, and we’ve been pleased with it.
Limited experience with the SIG 4XT. It seems OK for daytime use, it has a separate series of daylight and low light settings like an EoTech. However, unlike an EO Tech, if you switch out of night Vision mode and then come back, it does not retain your exact setting. It has 10 daytime and 10 night vision settings. If you’re on night Vision setting seven and you switch modes when you return, it will automatically go to setting 10. If you were on a setting in the lower half of the night vision range, you switch and come back it will not come back to your old setting, but will instead go automatically to the lowest setting.