So you are saying that dual 140x27 mm fans by arctic can actually be mounted on bottom, even if you prefer noctuas?I can only speak for myself, but I use 120mm fans in the bottom because I had two NF-A12x25 Noctuas and they are better than any other fan, 140mm models included.
In terms of CPU cooling, NH-C14S is still your best bet. BeQuiet offering is almost as good, but I think the reason behind his low use in Cerberus builds is the crappy mounting system.
And the 140mm fan that can be mounted on the front panel, has to be max 15 mm, or can also be 25-27?
And same for 27 mm fans, on the bottom of your c14s, instead of noctuas 140x25 can it allow a 140x27mm or 25 is already too tight?