Sorry for the delay in posting....
The Insight "Squared" (Version 4) was developed to be more aggressive than the V2.
The wing area was less, more taper and thinner airfoil.
The construction was designed to be very simple to build, using styrofoam parts and a simple wooden fuse-box.
The Insight V4 is a very light weight design (less than 4500g!). I used a YS140sport, and a OS160fx and both engines worked very well with this light weight airplane. It also turned out to be a great design for electric.
Here is the original build thread showing the construction of the plane.
http://www.rcuniverse.com/forum/m_2806566/anchors_2806566/mpage_1/key_insight/anchor/tm.htm#2806566-Mark
www.insightrc.com