Interesting, we had this coversation this weekend at the field.
My position:
If you "have to have" expo on your aircraft then in my opinion either the aircraft is too sensitive or you are not ready for that particular airplane and or you need more experience just plain flying.

Next sermon,
I have seen people fly planes that were way ahead of where they are on the "learning curve" and it never amazes me to listen to these people (men and women) that want to complain about an airframe "it doesn't fly very well" or "it's not very aerobatic" and they ask me to fly it and the thing is set up with expo at 30 to 45 percent, after the expo is removed and I or another one of the IMAC pilots fly it they really like it but they can't fly it and they either crash or sell the airplane.

Closing,
Just my opinion, and like arm pit everyone has one and no one thinks thier's stinks