At stock, sure, but what happens when there is voltage control, you want an extra 5-10% performance so you put the voltage up? The devil goes from 34.5dba to 40dba, the Nitro goes from 44dba to 52dba and the devil is still quiet while the nitro is actually loud.
10dba quieter means it will be significantly quieter when further overclocked as well.
I've said elsewhere, my main issue is they are identically priced but the Sapphire is simply badly designed. extra wide pcb, wider fans = empty space under the shroud, overhanging fans. You're getting more heatsink, more fan and less noise for the same money. If the Sapphire used it's extra card width and actually had a wide heatsink filling that space then it would be significantly quieter and run cooler.
They've hidden a 'meh' heatsink under a fancy shroud, they've tried to make the card look bulky and like it has beefy cooling but behind the fans you see they skimped on the heatsink. That is what puts me off more than anything, I'm getting better value and more heatsink with the Devil. The sapphire is shorter, though wider(so overall area isn't hugely different) and will certainly fit in some cases the Devil won't, but there is just no reason not to use up that space under the shroud for a bigger heatsink.
I don't agree the Nitro is badly designed as it's a real looker and has a premium feel to it.
Having said that, I do agree the Devil is the better card as it's a lot quieter and I want to push mine with overclocks, so those 3-fans are naturally superior to 2 larger fans in dissipating extra heat from the core running hotter.