yer the PA is alot better mate and if its not to much more then its worth it.
still the king of the rads as people say
Ok, Thanks a lot for the info

EDIT: Also I'm guessing you can mix around the size of fittings as long as they have the same barb size, e.g. the PA rad is 3/8 thread whereas the Water block is a 1/4 thread but both have 1/2 barb size in which will fit a 7/16 id tubing (1/2 barb - 7/16 tube recommended by tom is it not?)