if the case form factor is not an issue, then the Thermaltake Water 3.0 Ultimate is the best. 360mm, which means 3x 120mm fans, with a max rpm of 2000 on each fan, is the most powerful of all the closed loop coolers.
but at 140$
http://www.newegg.com/Product/Product.aspx?Item=N82E16835106241&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-na-_-na-_-na&cm_sp=&AID=10446076&PID=3938566&SID=
so it is up to you. keep in mind that water coolers are just as loud, if not louder, than an air cooler. they still use fans you know!