Generation IV External Engine - Which TB for Holley Dominator

I'm putting an LS2 intake on a LS4. I'm guessing these match. I'm overseas and purchase the parts and have them sent to the shop doing my project. The LS4 is supposed to have LS6 heads.

Anyhow...for the Holley Dominator DBW, there are two GM TB's that are calibrated for this ECU.

GM - 12570790

http://www.ebay.com/itm/05-08-Corvette-Z06-Gto-Throttle-Body-LS2-LS3-LS7-90mm-/320624624044?hash=item4aa6b781ac&item=320624624044&pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr

GM - 12580760

http://www.ebay.com/itm/2006-2010-Chevrolet-GMC-Hummer-Cadillac-Saab-Throttle-Body-4-3L-5-3L-6-0L-V8-/230718466226?hash=item35b7e468b2&item=230718466226&pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr

To start, are the bolt patterns the same?
Also, is either TB better than the other?
The second one is considerably cheaper-even to justify an adapter if necessary. But hows the reliability/quality?

I've got the "car" 90mm one ending in 790 on my LS using the dominator. You can usually buy them around $200 used on here. BE SURE to get the silver blade LS2 version, not the identical looking except gold blade LS3 version (probably different part number, just don't have it handy).