RE: 40 vs 60
My trainer was a Great planes PT 60. I loved this plane and it was one of the best flying planes that I ever had. This plane was given to me by my friend and flying buddy. It was built like a tank. He had glassed the fuse so the plane was a little heavy. I flew it with a Super Tigre 60 on it and it flew great. I have since passed this plane along to another friend who flies it every weekend. If it were me I would get the 60 size trainer. they are easier to see and they seem to fly better. This could be because you can see them better. All I know is that I would by another PT 60 if I needed another trainer.
Rick