Vepr makes a nicer rifle overall and probably the best Kalishnikovs anywhere, but they use a non standard receiver pattern, thicker barrels and proprietary parts which makes it harder to get the full value out of an AK74M/AK100 series rifle. For example they are a bit heavier, don't have a 24x1.5 front sight block and most don't have any kind of folding stock. Many are also slant back receivers which make it harder to add a folding stock, but lately there are a number of new versions with square back receivers that solve that problem. Advantage of the Vepr is the highest level of QC and attention to detail and they are generally considered to be more accurate. You are unlikely to get a lemon and almost no one complains about the Vepr. They also have a better side rail which allows the use of SVD mount optics like PSO-1s as well as classic AK pattern optics like Obzor, Rakurs and Kashtan as well as quality mounts like RS Regulate and NPZ
The overall most available, affordable and excellent quality rifle in 5.45 is the SLR104. They have a proper 4.5mm folding stock assembly, standard RMP3 side rail and the 24x1.5 FSB. They will run any AK pattern optic or side rail on the market. Downside is QC for Arsenal seems to have really slipped again and people complain often about them. By QC I mean attention to detail on the finish and if the sights are canted. I don't think I have heard of many, if any, serious mechanical issues. There is also a dedicated anti Arsenal group that does nothing but go after them, which can turn people off to what is generally one of the best 5.45 guns on the market. Arsenal seems to produce more than its share of rifles with canted sights but generally those are a relatively simple fix at home. Arsenals warranty service used to be horrible and few people seem to have had a good experience, so if you do need to warranty the 104 it may not be a pleasant experience at all.
The fixed stock equivalent is the superb SLR105 but they went out of production around 10 years ago and you won't see those except rarely. When you do they will be almost as expensive as the SLR104
FWIW I own 2 SLR104URs, 1 SLR104FR, an SLR105A1R and formerly had an SLR107UR. All were straight and put together right and I only had the chance to inspect the SLR105 in person. No issues with any of them. I've had the SLR105 for 12 years and put 10000+ rounds down range without an issue.
I may be lucky, other people have had issues with the 107s and lately the 104s
The SGL31 to me is a collector's dream rifle...a real AK74M pattern rifle made in Russia at Izhmash. It doesn't get better than that as a collector, but for a practical shooter I would recommend the SLR104 over the SGL31 mostly due to price and availability. The SGL31 is a great rifle but they are stiff and unpleasant to work with out of the box, and take time to get loosened up and broken in. The SLR104 is smooth and buttery out of the box, and a real pleasure to disassemble compared to a new SGL. Over time things equalize and it's difficult to tell them apart. One is a modern Russian version, and the other an early 80s pattern rifle. Both are equally effective in the real world.
On the question of 5.45 vs 5.56 in a SHTF scenario it may make more sense to go with a 5.56 rifle. In the US 5.56 is everywhere and everyone you know will likely have it as well. IMO SHTF is less likely to involve prolonged or common gunfight battles so I will roll with 5.45, but if you want true commonality 5.56 makes more sense.
And if you are really going all out SHTF quality, get the RS Regulate mount and be done with it. Other than the NPZ mount you won't find anything better but RS is lighter and easier to find.
Yes, with a quality mount you can effortless remove the optic without losing zero
Check out my site for more info
http://russianoptics.net
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