[quote="Michael
As soon as you are running turbo's that keep operations @75%, or high output motors vs CI's it turns into a horse of another color....
[/quote]
Actually, Mike, I usually use cruise power settings in the mid-60% range. 75% cruise climbs are done with full rich mixture.
Make no mistake, I'll lean agressively at 55% (or less), power if I'm in a "max endurance" holding situation. I certainly agree that there is place for LOP operation. A 4-6 gph saving in fuel for my airplane is not to be ignored, however, as Al says, it'll take me at least a year to recover just the cost of the GAMI's. Then there is the risk of me screwing up to consider...