RE: Golden Era 60
I've got both the 40 (OS .55AX) and 60 (Evo 1.00) Ultra Sticks and the Golder Era 60 is heavier due to the big fuselage, but flies well. I do recall the author saying he landed a little fast. The airfoil looks more like something from a racer. It will fly great if you keep it light, but with all the lumber in the Golden Era fuselage, it isn't going to be very light.
As for messing up the flight characteristics, check every acro plane around and you won't see an airfoil as thin as the one on the plans. As long as you keep the thickest point about 1/3rd of the way back, you'll be fine. I like a full symmetrical because it doesn't tend to change pitch with power. A flat botton and, to a lesser extent, a semi symmetrical, airfoil will climb under power and dive at idle unless you correct. For general sport and acro RC, a symmetrical flies better than anything.