Monty Barrett brought an excellent point to my attention that  deserves consideration.

<<<A big fault of (EI that uses manifold pressure to set timing) is that as soon as the engine starts and the manifold pressure is at a low value, the ignition event occurs earlier and all that is accomplished is that a lot of surface area in the combustion chamber confines is exposed to a lot of heat which is NOT doing any work.  I personally know of some ground overheats that occurred with (EI) because of ATC delays, long taxi's, etc.>>>

Admittedly, I do not know enough about the various EI systems on the market to know if this circumstance has been considered in the design such that the advance is appropriately set at low RPM (for ground operation). It is a question I would want answered when considering using an EI system.

Regards
Brent Regan