For me its a toss up between NPZ and BelOMO.
Generally i find the finish and aesthetics on the NPZ scopes to be better and more iconic. Most NPZ optics will come with a very nice glossy grey magnesium finish, which visually is more in-line with what is seen on iconic scoped rifles like the Tabuk Snipers, SVDs, PSLs etc etc. However this two tone clash between grey and blued steel may not be appealing for everyone. The NPZ scopes will also come with turret caps, and built in adjustable sun shades. They also IMO have a far more comfortable rubber eye cup, so much so that for every BelOMO scope i buy, i also order a NPZ styled eye cup to go along with it. Illumination wise, NPZ scopes all seem to use a single AA now. This is handy, but at the same time does integrate a rather large and possibly unsightly battery compartment onto the optic. I find the glass in NPZ scopes to be on par or slightly better then most Western LPVOs at a similar price.
The aesthetics and finish type on BelOMO optics can be all over the spectrum and its sometimes hard to determine what u will get. Depending on the model, and production year you can get the iconic grey finish NPZ mostly uses, or a rather nice glossy black, or a really coarse powder coated black that sounds unattractive, but actually compliments the look of modern red rifles and parkerized red rifles quite well. BelOMOs POSP line up tends to come in glossy black and the powder coat black, the latter more often being the case. The rubber eye cups that come with them nowadays look pretty cool, but IMO are far less comfy to rest ur eye socket against. Especially when its cold. The clarity of BelOMO scopes id say are on par with NPZ, however they do have an ever so slight yellowish tint. I personally prefer the reticles on BelOMO scopes over the NPZ ones cus i find the BelOMO scope reticles to be more fine and crisp. Where as the NPZ ones are more bold. BelOMO scopes tend to use watch batteries, which results in a much more sleek compartment design.
Both brands seem to offer similar build quality. Noticed however that the zoom dials on BelOMO are nice and tight like what ud see on Western optics... whereas the zoom dial on my 3-9x24mm NPZ scope is somewhat sloppy. It still functions perfectly fine tho, and this leads me to believe that thats just how NPZ builds it.
Note that ive differentiated scopes here. Not optics as a hole. This is because once u start considering Collimators n stuff, things become far more model based. BelOMO offers such a brilliant selection, but at the same time some of the stuff in that selection is pretty lack luster. Whereas NPZ offers an extremely limited selection... but most of what they do offer is considered top notch and literally fielded by Russian / Soviet forces.
As for the 400m "Siminov" reticle VS standard 1000m "SVD".... i wouldnt go far out of ur way the acquire a BelOMO POSP that has the 400m reticle thinking it will compliment your 7.62x39 gun well. In theory it should... but ive noticed with mine that i hardly utilize the BDC reticle at all. Plus the 400m optical range finder is for 1m objects... which possibly can be considered odd. What reasonable target is 1m high ? the back of a whitetail ? a bear ? a crouching Bigfoot ? The 3 chevrons in the reticle are supposed to be for 100,200,300 i think, but i noticed mine only has 2. maybe its the model i bought ? idk. Moral of the story is when shooting long range ive opted to use the metric elevation turret to reach out rather then the chevrons which eventually brings me to the same thing someone with a SVD scope would do. THAT BEING SAID THO, the 400m Siminov reticle 2.5-5x24 POSP has proven to be a very pleasant and dependable optic to look thru and i would buy again.
For my Tabuk project i decided to go with the NPZ PO 4x24mm SVD optic cus it looks kindov similar to the LPS Romanian scope I believe many Tabuk Snipers equipped.