Ive got an OCZ modstream psu in my Antec 900, i didnt have any problems with wire length, apart from the top 200mm fan, the 4 pin molex wire isnt any where near long enough to reach down to the psu but lucky for me i had extra wires with my psu when i bought it so i just used one of those.
And as above about the fans, they are really good and shift alot of air even on low settings. I have all mine on low, i find its quiet and it has still dropped my temps compared to my old case, my gpu is 8degrees cooler for example, so if i wanted to drop it further i could switch one(or all) of the fans to medium or something but i wont because my system is cool enough with the fans on low
And as above about the fans, they are really good and shift alot of air even on low settings. I have all mine on low, i find its quiet and it has still dropped my temps compared to my old case, my gpu is 8degrees cooler for example, so if i wanted to drop it further i could switch one(or all) of the fans to medium or something but i wont because my system is cool enough with the fans on low