64 cuda stock tank in tank pump?

From a quick look at the both of them, it appears the Specter will flow more fuel ,but I do not see the pressure that it provides , but I do see it has a return line. On the Holley ,I see it flows less, but it has a 58 PSI pressure, but no return line.
The Holley says it will supply up to 550 HP.
Do I believe the Spectre will equal that.
As my motor will be at that level.