The biggest challenge to building this airplane has been the delay in acquiring parts! Vans promised the avionics kit last week, still waiting for that after many dalays. Viking has still not furnished me the ECU, PSRU, or a bunch of other parts, so lots of time has been wasted waiting for stuff to build it with. I upgraded the fuel system, might be overkill, but I wanted something other than floppy hoses with clamps like a cheap lawn mower, I got a fire sleeved teflon stainless steel braided hose with the proper fittings made by Top Swearengen at TS Flightlines, just like a real airplane has. Now if I have an engine fire, I will have several seconds more before my feet burn off and I arrive at the scene of the crash.