So i enjoy playing with both a pad and a stick, but more often than not i'm on a pad (DS4) since the stick is noisy while our baby is sleeping. I finished up the character trials recently and was refreshing my memory with some others, but experiencing frustration at pressing analog triggers a fraction before I wanted to. So I briefly changed the config to use the face buttons for 2x P/K and noticed i wasn't having any trouble.
So i decided i'd pick up a Hori Fighting Commander pad, since it's got 6 face buttons and digital only triggers. It arrived last night so i put it through it's paces, and i'm thoroughly impressed! I'd read online mostly positive reviews, but a few people saying they had trouble with diagonals. No such issue on mine, in fact just watching the direction inputs on screen, it's much more precise than the DS4. The DS4 tends to show extraneous diagonal inputs, sometimes even multiples of the same input in-between a motion. The Fighting Commander is pretty much always showing just the exact inputs i want to press and nothing more.
As i hoped, having the 2x P/K buttons on the face of the controller has made long combos considerably easier to execute. The controller has a switch to swap the identity of the L/R buttons too, which is a blessing for KOF14 since i'm so used to pressing R1 for MAX mode, and the R1 button is now on the face and set to 2xP. With the switch, I can set MAX mode to L1 which is registering in the R1 position. The buttons are larger than the DS4 so they're easier to hit but close enough that you can move from one button to another on the other side quickly. The controller itself is light, but feels good in the hands; the handles are long enough to give good balance without forcing you into a grip.
Just wanted to post those impressions cause i'm just a casual player and normally struggle with consistent execution of long combos, but in just the short time with it so far, can see a marked improvement in that area, so maybe it'd help other players.