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.