As you probably already know, Lectron do a similar thing.
This link explains it a bit:
http://www.lectronfuelsystems.com/technical.html

I too would be extremely interested to hear from anyone who has tried either APT or Lectron carbs with the ability to auto-compensate over a range of air densities (temperatures and pressures/altitudes) to keep the fuel/air ratio effectively constant.
Gotta love that transparent float bowl.
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[color=#808080][size=9]Yes,.. I too know how to waste Time and Money,...