This article documents lower emissions at idle with HEI vs points

http://www.superchevy.com/how-to/67498-hei-coils-modules/

This article compares HP and torque in the 3500-7000 RPM range,, way beyond practical street RPM, with points vs 2 versions of HEI.

http://www.hotrod.com/articles/ccrp-9812-ignition-performance-test/

If HEI cleans up idle emissions it would be interesting to see what happens between idle and 3500 RPM

Ray