I carried my P09 once. I put it in the holster and went out the door.
I found out that little bit of extra length (butt end, not barrel end) had me bouncing it off all kinds of stuff in the garage and sheds. I guess I'd figured out exactly how to "slip by" those places with the P07 and must have just barely been clearing them.
Also, I wouldn't have thought it, but I could feel the difference in weight. Not a big deal, I wasn't walking far, but I could tell it wasn't the P07. I just put the P09 back in it's spot and went back to carrying the P07, but I do carry the P09 magazines most of the time. If I've gone through the 13 rounds in the gun I don't care if the magazine sticks out a little when I reload, and I probably need the extra couple of rounds anyway. Because I'm having a bad day by then.