As I noted in an earlier thread, I agonized for months over which EFI system to choose for my 1978 Camaro. Since I am not an expert on EFI, I started collecting information on four different systems then combined it into a matrix so I could make sense of all this. (This information came mostly from Summit Racing and the vendor websites.) I will say up front that I cannot debate the finer points of any of these systems... this is information that was readily available, just not in a comparison format that a layperson could understand. With all that said, here is a head-to-head comparison of four different systems. (Aka, MSD Atomic vs Holley Avenger vs FAST EZ vs Powerjection III). MegaSquirt added in May 2012. This product line is a different class of system due to installation and a high learning curve, but we wanted to display the comparison for those interested in it.) v4.1. Published 15 May 2012. I look forward to seeing where this goes, but as of now, I plan to buy the MSD Atomic. Notes: I should mention that the MSD 2900 includes a Fuel Pump, but is an additional $300 and I wanted to keep the prices as roughly equal as I could. The Holley HP EFI and Holley Dominator were intentionally excluded from this review as these products exceeded the parameters for the typical deployment scenario and end user that were established as the basis for this review. (ie, cars running at <400 HP.) I may add these products later, time permitting. MegaSquirt can be configured to control nitrous and can use most stock EFI sensors. It is compatible with electronic transmissions.