I got an MSI RX 480 Armor 4G OC (one of the cheapest 480s I found) a couple days ago. I can run at 1290/1850 MHz core/memory (stock is 1290/1750) at 1V (undervolt) in Wattman. Running Heaven benchmark my temps peak at ~69 C, with fans at a virtually inaudible 30%.
Alternatively I can OC to 1400 MHz core @ 1.145 V, temps around 77 C and fans at 50%. Very audible, but not to the point of being annoying in my opinion. Haven't had much luck OCing my memory further (although I haven't spent too much time on it yet); I tend to start getting memory errors (as measured using HWiNFO), and then sometimes crashes, pretty quickly beyond 1850 MHz.
Honestly, I question the value for money of getting a 'premium' card. I was just posting in another thread where someone was overclocking there XFX RX 480 GTR [strike]Black Edition[/strike], which I've heard to be the best/highest overclocking 480 out ther. And yet the results he was getting seemed worse than mine on my 'budget' card.
Edit: Was regular GTR, not Black Edition.