Note, that both of them are made by Katauri Interactive - a small, but very dedicated and creative team of game developers.
Also, these are two of the best games that I played in last 10 years, maybe (not the only two best games, though): Pathologic and The Void as they're known outside of Russia. Sadly, these two are too much depend on Russian language and mentality to be successfully released anywhere else.
PS: S.T.A.L.K.E.R. games are from Ukraine (ex-USSR, not Russia) and besides I don't count them as a best