I know what you mean by sorting out the BS from real life. I've seen a plane powered by a Saito 180 and get an engine swap to an OS 160. The 160 pulled a little harder and burned about the same amount of fuel as the 180. For your Edge you're looking at the 160 or Moki 1.8. Mecam here is running the Moki on his edge, and you can see some video of it on www.3dbatix.com and it looks like he is not lacking in power. On the full 3D video you can see him do what I think is the best method for starting the engine too.