I have the Meziere pump on mine and it flows 55 gals per minute. That is a constant flow and not dependant on engine speed. This rate is also higher than the stock flow which is, I think, 40 gals per minute at full speed.
It does require some mods to the '03/'04 Cobra because of the cross brace between the heads, but it isn't too bad.
It has been on my car for about 3 years and is still working fine, although mine is not driven on a daily basis.

Attached is a link to some pics I posted of the install.

http://www.modularfords.com/forums/r...bra-13589.html

From what I have seen and read, it is good for about 10 HP and provides additioinal cooling.
The only downside is the possibly shorter life span. Meziere figures about 3 years of constant use.

Dana