Beam :]
My old gym always had the same rotation, beam, bars, vault, floor. I loved starting out with beam for a few reasons, one, it's nice to get it over with. If you mess up, you have the rest of the beam to catch up. Two, it was my favorite event, and usually at the beginning of the meet I wasn't soo nervous because it was the first event and any mistakes you can just try to cover up later. Thirdly, I had knee issues, so it was nice to get bars and beam out of the way, then I could just have pain towards the end of the meet.
I think if I had beam any later than the 2nd rotation, I wouldn't like it because it's a lot of pressure to end with.