I'm not a big fan of pre-roll, I would recommend doing your own research by googling the pros and cons of pre-roll.
The fact that pro-roll is hated by a small percentage of end user
I always find the argument that some people don't like pre-roll and find it annoying an interesting reason to avoid it as a way to advertise. Who are we kidding? Most people are annoyed with any advertising. Why do people DVR to avoid commercials? Or switch radio stations at commercial break. The fact remains if the message is interesting or relevant to you and your needs you listen to it. If not you ignore the ad or are annoyed by it.
In any case I think now that pre-roll on youtube is becoming the norm and not the exception people are getting used to it.If done correctly through retargeting or highly targeted campaigns you can get some very inexpensive branding.
Not many places you can get your name in front of an in market shopper and have them watch 5 to 30 seconds of a why buy from us message for 0.13 a viewing.
Paul,
How often do you change your video pre-roll?