I really like Tarasenko, though admittedly I've only been able to watch full games of his at the last two WJCs. He has a game built for North American hockey IMO, he's very strong on his skates, seems unafraid of contact (huge difference from Filatov here), great hands, quite a good skater (not a "beautiful" stride, but very good acceleration and a solid, wide stance), fairly high all around skill level and a beauty of a shot, he's not one of these "all flash, no substance guys" that get teams in trouble, he does his work quickly and efficiently. Filatov and Zherdev comparisons are unwarranted IMO, he plays nothing like them. I see his upside as a sort of Radulov/Kulemin hybrid, mid way between the two in terms of skill, hustle, strength on skates, etc., hopefully with more of a Kulemin type personality.
There's always a risk with Russian players that they won't come over, but for guys with Tarasenko's potential, they generally DO come to the NHL. He's also had a few injuries, but I don't think they've been too bad - broken orbital bone and a not-too-severe shoulder injury if I remember correctly? If he comes over and is healthy, I'd be pretty excited about him as a Blues fan, seems like a very legit NHL talent.