I have a Decathalon from Pheniox and was having problems trimming. The club had me shim the front of the wing up 1/8". I am flying with a .65 K&B. CG is at recommended from manual. Flyes much better for me now. No meters were put on the wing just a dry wall sq to compare both. I do have 2 washers at the top of my engine mount and 1 on each side(due to it being mounted on an angle) to create the down thru. It is very squrilly on the ground so I abort take off if I can't get the tail up at about 15'. It does pop off the ground from there very easy.