Yeah I don't think its worth the noise imo. I'm a silence nut and am using a 212+ (24$ @ MC) on my 2500K and the temps are superb. Are your temps not within the norm? Have you tried a remount to see what kind of contact your getting?
Look at
this
I will say this about the 212+ as the base is not perfect flat...it's crucial to get a good mount or good contact. I've built a lot of PC's and this cooler is tricky. I've reseated mine twice now to experiment. I realized this cooler takes more TIM then what I was used to...firstly on the base to fill the gaps and then a 3 line method (the above benchmark link uses 2, but that HS only has 3 heatpipes) instead of a "pea". It's also important to equally tighten the screws going caddy corner to caddy corner when mounting like remounting a tire on your car :awe:.
I'm using an 800 Scythe Slipstream on mine it's super quiet almost silent inside a good quiet case and you can get them
here
You might want to be safe if your not a silencer like me and get at least the 1200rpm models or higher even, then you can control them how you like via bios, speedfan etc...
You can also use the S-Flex series they are a little more $, but are also very quiet. I have a 2 Noctua 1300rpm intake's and an S-Flex 1200rpm exhaust for my 3 case fans all at ~700 rpm while idle. The Slipstreams put out a little more wind at the same RPM from what I read...
The Noctua's and S-Flex you link are excellent fans