As said the D-Pad is better on the Xbone. It is personal preference at the end of day. But mechanically it is designed better.
I would say if you are focused on fighters then get a pad designed for them.
Other than that the triggers on the Xbone controller are much nicer as well. And the rounded edges of the outside buttons feel a lot nicer. I find I get a sore edge on my right thumb when I use the DS4 controller for more than a few hours when playing fighters.
The extra bulk of the Xbone controller seems to fit my totally average sized hands much nicer. And I find the handles on the DS4 to be a bit short.
And of course there is the squeaky weak plastic. The DS4 feels like it can be twisted into a pretzel if you get rough with it. Haha, salty pretzel.
PS... Sorry if this is a double post. My TYM is on the frits and crashes when I try post.