I'm planning on building a bike up around the frame and using it for cyclocross racing and road riding. I am torn between these two frames, the Demon is made of Reynolds 853 which should make it about indestructible, something I could depend on for years. But I don't know that durability over time is as much of an issue as it is made out to be for Aluminum. The Rock Lobster I am sure is lighter as well, but I don't know how much, if it's not too far and I can build a very light bike either way it shouldn't make a difference. Any knowledge or suggestions about either of these bikes would be very much appreciated, or if anyone knows a frame that they think is much better than either of those.