Control Line (CL) Handles 

To get a steady flight you want to have a smaller spacing between the cables. The wider the space between the cables the more it moves the elevator making the airplane more difficult to fly it level. I would suggest finding a handle where you can adjust the spacing or start with handle that has a narrow spacing. Every model is different some might fly well with a wide spacing while some really need a narrow spacing like my Spitfire.

I have numerous handles that I fly with, but my pop always uses his old trusty plastic Sullivan handle he picked up in the 60’s. Yours is yellow, his is red.