@alis what helped me pick up controller targeting was basically: l2+r1(or r2+l1) functions as tab target, which is the easiest way to get an enemy targeted.
d-pad targeting is whats called a "soft target" and you can turn it into a proper target by pressing cross. soft targets persist for exactly one action and then snap back to your previous target. I only use it for targeting party members (up and down) personally.
@kip I... I did not know that was the difference between left-right/up-down on the d-pad. Holy shit that makes things so much easier, lol.
@alis targeting is what keeps me on mouse and keyboard for most 3D games - FPS, MMO, Third Person, it doesn't matter, you can't beat the responsiveness of a mouse.
Or at least I can't.
And it sucks, because a controller is better for most other things outside of RTS.