It's funny because Microsoft are the only major player in the gamepad game that still make non-symmetrical sticks. Sony use symmetrical sticks, Nintendo use symmetrical sticks (both on WiiU gamepad and Pro controller), Valve will be using symmetrical "sticks". Personally, as a person who has owned all of the major non-Sega consoles since the NES, I think the symmetrical layout is way more comfortable. But then again I don't use gamepads for shooters, I tend to play those on PC.
The DS4 is quite different than the DS3, and significantly larger. Quite a bit of the "narrative" about the Xbox controller being worse comes from the fact that the shape has changed, the insides of the handles are sharper and thus not as comfortable.
Seriously mate, that narrative came from someone who had never touched the X1 pad. They've looked at a photo and made a bad inference.
The only edge on that pad is on the top front of the grips. Your fingers get nowhere near it. It's a purely aesthetic design choice.
I mean really, just imagine fingers curving all the way around the pad and gripping around the front edge! Even as someone with freakishly long fingers that sounds absurd to me. You'd need to bring your fore finger around to achieve that grip, rendering the pad unusable.
The entire back of the pad, the part you actually touch, is contoured and curved, just like the DS4 but both in different ways. The DS4 is more like the 360 grips in that you grip around them, the X1 grips are designed to spread your hands out more openly, and while I liked both pads, and both were comfy, the added comfort of the grip style of the X1 pad was much more to my tastes.
That's what it's going to come down to - taste - both pads imo are better than the 360 pad, which was very good. Some will lean to one, some to another, but any objective party will agree both are good.
When I read people saying one or the other is trash, having tried both, I just mentally mark them down as a console war-ist and move on.