I have the C14 and U9B and the C14 cools my components much better with around the same noise level. The C14 setup uses 3 fans instead of 2. I know it's not a direct comparison to your ideas but that's been my experienceI'm having the same idea, no doubt that the 120mm fan is superior compared to 92mm but thinking about tower fans able to direct exhaust hot air out vs top down fans (Into the casing ) given the two heat sink Noctua U9S and C12 weight 528g vs 550g (almost similar in weight and surface area),
1 top down , it can draw in fresh air from the side bracket directly and a fan can be attach to the rear casing as an exhaust,
2 tower with fan mounted horizontally , a fan can be installed on the side bracket ( psu side ) to draw in fresh air.
I can't decide which is better.
Has anyone compared both ?