You should have no problem at all with that setup.
Intake or exhaust you're going to be dealing with warm air rising from the 480, nature of the beast. However out of the 2 intake is probably marginally better. After a bit of experimentation with my H100; the reason there are so many conflicting opinions on intake vs exhaust is that the difference is minimal
IMHO, unless the temperature delta between your internal and external air temp is extreme. Which it rarely is, unless your case is chock full of components(SLI+RAID etc) and a significant overclock.
Of course you want the coolest air possible going over the rad, but don't go losing sleep over a couple of degrees.