i've got a stuff from last year and i love it. although it's listed as a DJ bike, its more of an all-round freeride hardtail. it's not the best in urban or hardcore DH, but it does handle well in all conditions.
the scrap is similar to the stuff but it doesn't have the same strength. the frame is slightly different and slightly less strong so it can't withstand as much as the stuff can.
in my mind, i'd go for the stuff because it has much more value than any of other other bikes in the kona DJ series. if you compare the scrap to the stuff, you'll realize that you get a much better bike for only a couple hundred bucks more. if you compare the stuff to the roast, you realize that you dont get much more for another 600 bucks or so.
if you're interested in checking out other bikes, i'd recommend the norco sasquatch. its a bit more than the stuff but there's upgrades in several components that make it worth it.
before you buy, just check out the bikes at the LBS and see which one fits your riding style best.
good luck!
BTW...post your riding style so that we can give you some more suggestions
*********************************************
Building a jib? Need some help or wanna give others some too? Then check out the Build-a-Jib cult
HERE!