Yes, they do kick ass. Some are even god-like. There are rumours of bud-busters that have a little chamber under the nail part... a chamber that will collect the really tiny shake and crystals that fall off the herb when it gets broken up. So, you let that chamber fill up over a month... then you get a really fucking potent joint out of that shit.

That's what I want to get soon. I have not seen one personally though...