Saw them on a 33% H9 Extra, but not on the tips, in the middle of the wing like a ST.

I did the F1 Spoiler/Wing thing on a Vision, like CPLR did on his pattern bird and it KE so much better now. Slow and fast, but it doesn't require the rudder some SFG planes need to turn.

Sorry I don't have a better pic, hmmmmmmmmmmm?

Just kinda eyeballed the size, I donno, however it works.