TweetSome companies cater to the flashy/show croud, so I imagine they do get kinda pricy. I've never had anything but Vortex. Vortex is a company that caters striclty to racing. Vortex has some nice write up on how their slider puck is "engineered" of a composite that's proven to slide better with less friction and/or ashpalt catch/grab. You can grab a set of Vortex mounting kits & pucks for like $60. and a 60 dollar bill spent very well bro. I have a skint left puck right now that saved me...who knows how much $. But sliders will save some really hurt feelings for not much $. I ride better with them too, because they give me that piece of mind. Ya don't worry as much, know what I mean?
As for the rails. Those are for stunting. They really stiffen up the frame, and keep the bike together longer than just a set of sliders.