Some thoughts.
The Sapsan is a new gun with not even one review. It has no safety and uses it's own barrels instead of using a LW or CZ barrel. Reliability is an unknown. For those reasons I would only consider it at a considerable discount to the established airguns.
Good luck.
Reviews:
https://www.youtube.com/watch?v=VdsiYKSF2M0
https://www.youtube.com/watch?v=d_AjZQDxRmc
Sapsan has changeable caliber/ barrel probe kits, so one gun you can have 3 calibers, from initial reviews its a tack driver...Watch out for Shooter 1721's Channel in a week he will release the Sapsan Review here is the FC Model using the same Barrel :
https://www.youtube.com/watch?v=wk-Ou0sxYuU
Here's a preview of what the Sapsan can do:
https://www.facebook.com/rick.rehm.5/videos/2630807437041854/UzpfSTEwMDAwMTMyMjg3NjkzODpWSzoxMDc0MTY0ODgyOTY0MjYx/ https://www.facebook.com/rick.rehm.5/videos/2630461197076478/
None of those are reviews of the Sapsan. The first is a dealer talking about features not even shooting it. The second is just a hunting video with almost zero information. The third is a different gun.
From feedback of their previous airguns the machining and finishing refinement is not same level as the major established brands.
There have been fairly good reports on other models accuracy which is encouraging but the Sapsan is quite a bit different. For one it has a long thin unsupported barrel. Guns with similar designs are known to experience POI shifts when the barrel is bumped which isn't hard to do during transport or say when bumping the suppressor into a tree when swinging it around in the woods.
I'd at least wait for a deep dive extensive review before laying down that kind of cash.