Why would I buy links if they are invisible to users?? Isn't the whole point of a link driving relevant traffic from another channel?
Oh wait, you mean people buy link for the sake of
PR? Yeah, I forgot.
No thanks. I'd rather provide quality content or tools to make people want to link to my sites and increase the
PR this way.
PR shouldn't be the cause of anything but the reward.
That's my 2 cents. Now, as long as there will be people buying links, there will be people selling them so I don't blame you.
While you are at it, you might as well link to
this website: it's kinda of the same business model