I'm no 3-d shooter, but a buddy of mine is always complaining about guys who have ways of "ranging" targets on the 3-d course without a rangefinder: i.e., counting the footsteps of the group in front of you or marking the focus knobon their bino's with the yardages.

To be totally honest: I join every contest I can, just for the fun of it. I don't get mad when people cheat, b/c I expect it. In some ways, I enjoy it - because it makes the whole experience more entertaining. In some ways, it's really pathetic that anyone would cheat, but in a weird way, it's actually kinda funny. It adds a new dimension to the whole experience. It also makes the victory even sweeter - knowing that you beat guys who were really trying to pull out all the stops for the win.