Time
I'd say the wings are the fastest, then maybe the tailcone, then avionics (faster if no problems), then powerplant, fuselage, and the finishing kit usually means you're half finished. Van's total of 800 hours to 1000 is not far off. Alot depends on whether you want to be a beta tester or not. Regardless, its an amazing kit and truly fun to build. You can do 99% of the work by yourself at your schedule with minimal tools.