These PMs don’t bother me, and I do read them. I don’t always answer because I don’t always have an answer. No answer from me probably means “maybe later”.
I always look at new offers though, be they through PM or mail. Often I do a little research based on the PM and make a quiet decision.
Really, I should reply more often, and would like to as a courtesy, but at times it gets abused and turns into hot pursuit with heavy sales pitches and I don’t like these.
So, like with a lot of things, the misbehavior of some hurts the rest.
But basically, it can’t hurt to send me a PM and it just might work.