Wolski has decent size, but he is a bit of a perimeter finesse player, who doesn't always like getting his nose dirty. Remember Kris Beech? People loving his size, wheels, and soft hands. But if you watched him closely, he was a bit of a perimeter player. Same thing with Buffalo's speedster Afinogenov. Some called him the next Pavel Bure after a dominant WJC performance back in the late 90's. Again, he skated circles around everyone on the perimeter but couldn't score inside.
Not saying that Radulov will be a better player, but he's more willing to mix it up, get his nose dirty, and is less of a perimeter player. Not to say that he's a power forward or anything.