Ussr / Egpws
I agree with H.Finn.
we had troubles with terrain warning using QFE on few airports only.
Usually a call to Honeywell solves your problem after the next database update!
As you know, flying in russia might keep you busy, (seldom flights to russia, language, navaids, procedures, young collegues.......) then good luck on your maths. What is the higher risk if you are well prepared??
Let them spend the money and provide us with well consistent databases!