Well, in my experience, they aren't that great for dirt jumping. I rode one for a little over a year, along with my brother and a good friend of ours. In all honesty, we found the to be to light. Hard to put into words, but they are sort of 'unstable' once you leave the lip. Not bad for just general stuff or racing, but most tricks were ackward at best. Plus, they are incredibly weak. My brother put two cracks where the seat stay meets the top tube, and my friend crack the dropout completely off.
If you are serious about dirt jumping and don't plan on racing, I would recomend you either trade or sell the ELF frame and acquire something like a DK, S&M, or Standard dirt jumping frame.