i found one loop gave me better temps but i was under using the cooling potential of one of my RADS.
there are some good kits if you search around, cant post to a competitor but google watercooling should give you some ideas.
one thing to remember is buy the best you can afford, a decent pump will last you through a few setups and allow for expansion, ive found the RADs ive used (Xspc, Feser, thermochill and HWlabs) all to be very similar in temps (about 5C) but you will have to use different fan speeds to get the same temp so if your looking for quiet operation its defiantly worth going for the bigger and better RAD