Okay, people who've read Doom Patrol, which of these should I make my new avatar?
This one?
Or this one?
I don't think the omnibus has any bonus stuff besides the foreword. I just checked the back real quick (didn't check thoroughly because I didn't want to accidentally spoil myself) and I didn't see any bonus material.
However, one other thing to consider is that the TPBs have that cheap newsprint-type paper, so the colors are going to be pretty dull. The omnibus has typical glossy paper which makes the colors pop much better. Not sure if that makes enough of a difference to you or not.