Whatever EFI system you buy today will be obsolete in a year (maybe less) and may not have service parts or tech advice available in a few years. And remember, these retrofit kits share the same intake problems as carbs and are about as antiquated as carbs.

In the end, a well-tuned carb would be much cheaper and perform just as well as any self tuning EFI out today and be serviceable long after the EFI is in the trash. About the only real advantage of a retrofit EFI system over a well tuned carb is maybe a little cold start convenience. Beyond that, a properly sized carb in a competent tuners hands will perform every bit as well as any self tuning throttle body EFI. But most guys buy a carb, slap it on out of the box, and then feel that they need to spend cubic bucks on an EFI system because the carbs doesn't perform well.

Now there are real advantages to multi port EFI with timing control. But that is unrealistic for most of us for a number of reasons. And then there is still the very real possibility of lack of service parts and tech advice in the foreseeable future.

Retrofit EFI systems may eventually come of age, overcome it's current shortcomings, and offer real advantages over carbs for the average guy. But that is not what we have today.