Have an opportunity to buy a 50m ivgc.
Looks like this one:
https://www.google.nl/search?q=diana...v_hBCuZnFRVNM:

but seems to have a tunnel for front sight instead of the ramp and has dark stained stock

How do they shoot recoil wise? Are they accurate?
Any known problems to look out for?
Would be used for informal target work.