You want performance, then 120mm will kill the 140's. You will definetly want a good 120mm fan. If noise isnt a concern then i would go for a yate loon.
hey well since i have the same question , whats a good 140mm fan thats really quiet and has decent airflow, and also looking for a 120mm one thats quiet also.
Unfortunately they do not have 140mm fans on their list. Generally speaking the 140mm fans run a little bit slower than 120mm fans but still push the same amount of air. The end result is lower noise. My Dragon Lord case came with three 140mm fans. Those fans are much quieter than the fans on my cpu heatsink and video card.
I don't know about 140's, but I have had several Thermaltake Silent Wheel 130's, and they are just that, silent. It may not fit in some cases, though, as the holes are for a 120mm, but the sides extend a bit outwards.
im looking for a 140 to go on the top of case as exhaust , but either way when im gaming its gonna be loud cuz i turn my fans up. but what bothers me is the stock ones that came with the antec 300 case are pretty loud and make like a buzzing, humming sound which annoys the hell outa me.