Holley Sniper vs. Edelbrock Pro-Flo 4

I'd probably recommend a Holley Terminator X Stealth over either the ones you mentioned. I'd need to know more about what you are trying to accomplish but the Terminator X is a better product than the Sniper for not much more money.
Terminator X and X Max Stealth 4150 - Holley

This is what I was getting at earlier. These systems use the Holley HP computer. Only the sniper has the integrated computer. There are (were) basically two Holley computers---the HP and the Dominator. I think there's a new bigger one now. Regardless of what they "named" the rest of the systems, everything current except Sniper used either an HP or Dominator