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As Kevin mentioned, there is evidence that running at 100 ROP may be the "wrong" thing to do.
Here is my take on that. In the articles I have read by the LOP proponents, they say that the power setting in the 50 to 100 ROP area are where (1) the effective timing of the combustion event is most retarded, leading to the highest cylinder pressures and (2) this causes correspondingly high cylinder temperatures (note that cylinder temps peak before EGT peaks). Therefore, they conclude that this is the "worst" place to run the engine.
On the other hand, this setting is typically very close to "best power" as published in the POH's, and most performance charts show running the engines at this setting for best power. Also, because the power curve is fairly flat in this area, individual cylinder's will likely be generating closer to the same power, leading to smoother running and less vibration. The POH's usually recommend a maximum sustained cruise setting of 75% power.
On the face of it, the LOP guys appear to have their facts straight. They have proven the data on the test stand, and I have not seen any data which contradicts their published data.
On the other hand, I don't think you can make the across the board statement that this is the "worst" place to run the engines. As I think most everyone now agrees, as long as your CHT's are under 400 or so, it doesn't matter what you do to any great degree. If the engines were designed to run at this power and mixture setting, then it should be OK to run at this setting. I think this is where the 75% limitation comes in. I would imagine that the engines are designed to run at this power and mixture setting to simplify engine management and protect the engines, because any change richer or leaner from this "design point" would actually lead to lower temperatures and pressures.
On the other hand, if you go to all the trouble of getting instrumented, educated, and do run lean of peak, then you should be able to run at sustained power settings greater than 75% while maintaining equivilant temperatures and pressures. Doing this should be fine as well. However, there would be more room for pilot error, as enrichening the mixture from this point could lead to operation at temperatures and pressures beyond the "design point" and possibly induce detonation.
PS:
Returning to the subject of the engine monitors, I emailed JPI for a little info. They said they had no plans at this time to incorporate MP and RPM into the 760, or come out with a twin version of the 800. Too bad. On the bright side, they said they would be offering a $300 discount on units purchased at sun-n-fun. But, it's still a lot of money <sigh>.
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