Pretty much all of them are low noise and high performance, especially for the price.
Ninja and Mugen are top tier
Fuma is their "mid-range" -> damn solid performance though could use better/quieter fans
Choten and Shuriken are low profile
The rest is budget / out of date
Thing is, let's say it's Noctua - I know immediately that the NH-D15 is the absolutely lowest temp I can get from their range. I also know that Noctua aims at roughly the same level of noise across their whole range so a D14 will be slightly higher temp, higher noise, in return for size. D12 doesn't exist, but it's the same deal there. S12? Single stack. Same tradeoff. Etc etc.
With Scythe, I have no way of knowing which of their coolers is their absolute top-performer. The Ninja is, I **THINK** a larger, lower-fin density product than the Mugen, but I don't know if that means lower noise or lower temps in practice compared to a Mugen, since I don't know if the fin density of a Mugen makes it "Louder but cooler", or if they have identical fin density - in which case the Mugen is as to the Ninja, as the D14 is to the D15.
It'd be nice to just be able to look at their stack and say "This is cooling at all costs. This is low noise optimised. Ne'er the twain shall meet."
This isn't a problem just with Scythe - Thermalright has exactly the same issue with their stack and their naming schemes.