Most Blues prospects are underrated by the masses, so it's hard just to pick a few.
But, if I had to choose, I'd say that most underrted Blues prospects are:
Trevor Byrne: The resident Worcester expert here on the boards says that he'll be a #3 dman within a few years. He should get his first taste of the NHL next season.
Alexei Shkotov: Undersized, but has loads of offensive talent. A lot like Hudler, actually, even picked before him in the same draft. Yet, somehow Hudler is the great prospect.
Shawn Belle: Yes, he's a high risk guy but if he was a member of a few other organizations people would be touting him so much because of his raw talent.
Konstantin Zakharov: Was always accused of riding the coattails of Andrei Kostitsyn but has proven in his first year in the Q that he has his own talents.
There's a few others, but those are the main ones...