Hey Buddy,
They are all quite good with equal gains. The difference comes down to ease of installation and fit and finish. The Edelbrock is bar none the best of the best on fit and finish and performance as well. The Magnacharger is a close second. All comes down to your budget. I can give you great pricing on the units, especially Edelbrock. Just shoot me a PM or give us a call.
Thank You
RDP Store
440-358-5500