The product seems to be very well made, as said in a previous review there doesn't seem to be any problems with the symbols wearing from the stickers. As mentioned a few of the symbols are not in the bottom right, but in the bottom left (this is over Q, E and M keys on qwerty my layout), this doesn't cause any problem on my keyboard but it is worth checking yours before ordering.
The stickers are somewhat easy to apply for those with good dexterity. It may take a few attempts to get them lined onto the keys correctly though, good luck with that! There is one piece of advice I can offer, given that no instructions are given with the sticker sheet, it's worth putting your input language into Russian and testing the keystrokes before applying the stickers. The stickers are in the right order on the sheet but it's not clear where exactly they should start and finish on each row of keys.