Walter,
  I bought my Lightspeed ignition primarily for cruise performance, since that's where I spend most of my time.  Based upon what you said, the advanced spark it provides is a good thing.  Since the LSE doesn't advance the spark at WOT with high MAP (low altitude) I don't see how it hurts the engine.
  I'm eagerly awaiting PRISM too, but in the meantime, my engine runs great with one EI and one mag and I've never seen the slightest indication of any detonation.
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