I bought mine used. It had 12 flights. Builder was a noob at composites. In your build, be sure to do proper bond prep for all composite bonds. I swore up and down at what a rookie job the builder did the whole time I set it up for myself. My first flight was almost with a mffed 'tude and an expectation of a crash.
50 flights later, it is the funnest plane I have ever flown. It prolly weighs in around 37 pounds. I can do four snaps on a vertical upline, and fly away with some speed. It has a very small amount of yaw coupling with rudder... the good news is about 3 to 5 percent mixing will make it Knife perfect. The mixing is linear and perfect for all yaw conditions. It is a plane without flaw. It has a longer tail moment then my Super Extra, so it is very smooth in low rate.
It has two issues you need to be aware of.
1) If in a harrier, rolling harrier or other High Alpha maneuver, if you allow the nose to drop, it takes immediate and aggressive action to recover the high angle. Solution: Learn how to not let the nose drop. (In all honesty, I compare this to the Super Extra. It will recover the dropped nose INSTANTLY!)
2) In inverted Harriers, if you get the nose above about 65 or 70 degrees, it will stop moving along, and it will want to pitch the nose straight up. You will need to be very aggressive with left rudder and not be afraid to pull the nose back down to some angle less then 70'ish degrees with UP elevator. It does not happen suddenly, but it will do this if you allow it.
As I mentioned above, I have 50 flights on this plane in the past few months. I was flying a Super Extra, and even now I can't believe I like this plane as well as or better then the SX. (220 flights on my SX!)
Pictures here;
http://valleyflyers.com/gallery/Misc...smaller?full=1
and
http://valleyflyers.com/gallery/Misc...smaller?full=1
The stock ARC does not have 3D sized Control surfaces. Mine have all been enlarged. There were no special actions taken to make a proper CG.