Considering they're more expensive than getting a TR24T, Aimpoint H1, and mounts for both at MSRP, the performance isn't exactly mindblowing.
Eye relief IS garbage on the TA31/TA01, and getting a good field of view is basically the only tradeoff. This is the optic that made me love the UBR, but that's the only stock system that seems to work well with an optic that is low, picky about having eye relief, and has fine enough telescoping adjustments to work well in standing, sitting, and prone. Smartly applied electrical tape to 2/3 of the fiberoptic setup actually fixes the brightness issue
Personally, I run those things really fast up close (on a clean Table-III shoot, I was still finishing up strings of fire faster than the idiots who sounded like they were just point shooting and blasting), and despite that I'm still convinced there are truly superior options if you're not interested in having an M4 clone build (I have one with an M4A1 SOCOM profile barrel and TA31RCO-M4). I really like that rifle even though it's a 10lb boat anchor (UBR, TA31, A1 barrel, M4RAS) loaded; that said I have a much simpler rifle (DD V5 LW) running a TR24RT optic that does all those same things, and a few critical ones a lot better at a complete weight of 8.5 lb loaded (better up close, longer handguard means better light mounting, points better due to lighter overall weight), so a lot of my dismissal of the ACOG as a platform is related to that difference in functionality of complete weapon systems.
It's a perfect military optic for riflemen because it means having the ability to identify objects at distance and make solid hits at range, it has pretty gruntproof dual illumination, and critically it's as tough as the rifle it's mounted on, which is why the DoD spends as much on those as they do on the M16s they live on.
عندما تصبح الأسلحة محظورة, قد يملكون حظرون عندهم فقط
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Semper Fi
"Being able to do the basics, on demand, takes practice. " - Sinister
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