I did 4 batteries today although more than 4 flights. I spent the first 3 batteries going up then landing while trying to get the mixes just right for knife edge flight using only the rudder.

After around a dozen flights I finally have it set to Knife Edge! I had to mix in some opposite aileron and a bit of down elevator. Now I can just roll on the side and knife edge perfectly straight.

I lose altitude relatively quickly when doing it though despite the fact that the nose is pointing upward a fair amount. I'm using a Park 450 and 10x8 prop, would a prop with less speed and more thrust give it a better chance of keeping altitude? I'm considering trying a 11 x 3.8 just to see what it would do.