Haha, I know some chinese as well as I used to learn it for about 2 years, and indeed due to the multiple tones and dialects it is difficult to remember, but what is easy about chinese is the fact that almost no tenses are ever used, but this compensated by the difficulty of memorising the characters.
If you think 4 different tones of mandarin is sometimes confusing, you should try taking up cantonese dude, they have like 10 tones LOLOLOLOLOLOL.
Russian on the other hand is the reverse of chinese, the characters are relatively easy to remember, but there is so much grammar that you'll drown in it :p
Considering the fact that China is rapidly developing and strengthening its economy, it is a very wise move to learn chinese actually.