>>64106532
I prefer the 512 to the Aimpoint T2 (which is even nicer than an Aimpoint Pro) but it really depends on how much space you have on the gun and what your tolerance for weight is. 512 has better glass quality, a much bigger window and I'm personally a fan of the reticle. They are kinda big and clunky though. I think the battery thing is a moot point because I've had a T2 run out of batteries in 4 months because I left it on a moderate brightness setting of 10 (whoops). I wouldn't touch a 30mm ring red dot with a 10 foot pole in 2025 unless you like doing retro guns, they're just a headache and obsolete

>>63795012
The MAC MP5s are sketchy and the PTR-9s are apparently out of spec because they don't have the TDPs. Supposedly the Zenith US-made MP5s are good but I've never known anyone personally who owns one so I can't speak too much on those. Most people tend to own the MKE clones and I've owned an MKE AP5-P. Oiling the hell out of it, replacing the extractor with a German one and only using MKE or HK mags has given me 0 failures in 350ish rounds of Blazer Brass, even with an 80-degree locking piece. I would recommend an MKE if you aren't getting the HK. Just remember if you go to SBR it that the country of manufacture is Turkiye and not Turkey from the dropdown list and that MKE is the manufacturer, or the ATF will deny your form