I absolutely abhorred the lock-on camera when I played the beta, because I felt like I had zero control over my positioning or being able to see my surroundings relative to the monster and my position, something that's extremely important in a MH game, especially when you want to target specific parts.
The target camera, also available in the game, is definitely the more superior option as it allows quick focus to where the monster is, but doesn't wrest control of your positioning and camera movement from you. And honestly it's way preferable to having to keep controlling the camera with the right stick all the time too.