Intercooler Endtank design questions....

[BlackZenkiS14]

Ok, so i've narrowed down my Intercooler search to these two intercoolers. They are both the same size core (24"x11"x3") with same inlet/outlet diameter(2.5"), and same bar/plate design.
They are the exact same core, but the endtanks are designed differently. One is more squared off, the other has some curve to it...

Why are they designed differently? what are the benefits to each design? and which one would you reccomend?

Rounded/Curved
http://s1.promotionsupplies.com/ebay/etdmotors/images/ic/au-ic0048-1.jpg

Squared off
http://www.gooddealsfinder.com/ebay/etdmotors/images/ic/au-ic0016-1.jpg

[thetopcow]

i would think the rounded tanks would have less turbulance and better flow...but i dont think it would be enough to base my decision on. i would just go with the better price. but hey i am sure someone who knows more about intercoolers will respond to this with better info