SHEPARD - no idea.
KALINKA - WHICH MODELS? - I went to the Russian factory thet makes the PPO sniper models and obtained samples via a friend in Moscow. Better than baseline Asian - but NOT top slot - really not much better than high-end entry level.
I tried a 5-20*50 - This is a fixed image scope (i.e the reticle is NOT image centred) and you'll NEED to pre centre in adjustable mounts. The reticle ilumination is badly designed - and when I suggested the factory look at how anther russian make tackled the subject they quickly agreed that the competition was WAY better.
Also have a 6-24*60 (moving image) - OK - but loses clarity at above 21mag. Told however the fixed 10*50 is not bad (this from my mate who uses a PR-VX3 GEN2 MILDOT. Comes down to spec's. The fixed is simple design - and when I get news that my mate is coming over this way - I'll get him to bring me one to play with.
This is TRADITIONAL OPTICS TERRITORY - High lead content glass (HEAVY) and old fashioned coatings.
I also use a PILAD 8*56 a fair amount - very simple and unchallenged design so it copes well with simple glass. But this I doubt is what you meant. I use it for closish work - bunny bashing etc.
I've seen worse - but also alot better. For serious long distance - NO WAY.