Mike,
You know my opinion on leveling.......you want to take advantage of every opportunity to have your rig properly adjusted for every possible shooting scenario. IF a properly adjusted 3D axis means the difference between a consistent 2" right miss and a dead center hit on an uphill or downhill shot, I want that knowledge and precision.
Do you want to be standing at Worlds looking down a 30 degree slope wondering about your leveling? And if you don't bother to properly understand and use a sight with 2nd and 3rd axis leveling capability when you wing one a few inches either way who do you blame?

Here's some good 3rd Axis leveling reading:
http://www.spot-hogg.com/newsletter1.shtml

http://www.spot-hogg.com/newsletter19.shtml

Give yourself every accuracy advantage you can in your equipment. When you can 100% trust that your bow will put an arrow where you are aiming , up down or level then that part of the equation........trusting your equipment/sight.....is no longer a factor.

When you think about how much $$ you are about to spend on a season of local, state and Triple Crown National shoots, does it seem unreasonable to drop a few extra bucks now on the best equipment you can afford to put you in a position to be as successful as your bow will allow.

I for one will NEVER skimp on a good sight.