What coil are you running?

Just wanted to know what everyone is running for a coil. I was going to do an experiment and convert to electronic ign w/ chrome box, from my HEI setup. I know most will ask why, and the reason is simple. I do not think the HEI is allowing me to rev past 5800rpm. I have tried different fuel pumps, carbs, Dizzys and even had just changed to a MP .528 solid and it still does the same thing.
So, with that said, I have an Ecoil that I use with HEI, can I use it in conjuction with a ballast resistor, or should I run a MSD coil or something else?
Thanks!