I have no idea how you manage to get so fast on a megaminx. I have the original (and confusion) color scheme of the QJ stickered megaminx (DealExtreme) and I can't get below 8 minutes or so I average 35 seconds on the 3x3x3, but the megaminx as so many colors, it's confusing! Well, congratz!
I have a very apparent look ahead problem on the megaminx. I just can't find the pieces I need! Even if I were to go incredibly slow it wouldn't matter. Another problem is just lack of practice. I'll look for some more local competitions and if I don't see any within a few months I'll probably learn memo for BLD (I know the "technique" per say), and work on my 4x4 and the minx.
And I'll probably put my 2x2 back together if anybody from this comp remembers me breaking mine and asking people to borrow one.