And that's why this question comes up about every two weeks.
Do a search and there are several LONG threads about it.
I do a combo fo both, thumb on top with finger in front.
AMA#47402, IRCHA # 3395
Blade CP "Pro", Trex 450SE, PiccoZ, Quick of Japan EP8v2 EX, Hurricane 550, Hurricane 200, JR Vibe 50, Blade mCX, Bergen Intrepid Gasser, Pantera 50, Blade mSR, Novus CP