Performer is made for running from idle to 5500, RPM is 1500 to 6500. If you're shifting at 6000 or 6100 then I'd say get the RPM.
I have the RPM and it's great. I don't know the difference between it and a Performer because I've never ran a Performer. Oh yeah, but there's a slight difference between our engines, mine's carbed. So I can't tell you which one is better for you, but I'd guess the RPM for your application and driving habits.
------------------
'69 Coupe with 351W
=========================
Edelbrock Performer-RPM intake manifold, Edelbrock Performer-RPM cam, Edelbrock lifters, Edelbrock 750 cfm carb, Accel coil, Moroso Blue-Max spark plug wires, Hedman headers, 2 1/2" pipe, glasspacks, Edelbrock double roller timing chain, Edelbrock valve springs, Flex fan, C4, Lakewood traction bars, 3:1 open rear-9" 3.89:1 posi coming this summer
=========================
|