Use this one, I have made many great waterblocks with those.
Yeah, go for it! I think these blocks could probably out perform the #rotor block. And you only need one loop. Dont complicate it if you dont have to, especially if you are only using one small radiator. Personally, I'd make an extension on the case and put a larger rad up there. Or you can put a larger rad on stilts on the top of the case kinda. You wont see much performance with an 80mm rad.