Having an awful time ftping from work to procooling; was trying to post a smaller version of the graph for your perusal. FINALLY it loaded:
Points are averages (from 8-10 runs) and error bars represent std. deviation (from those runs). Note (a) the excellent performance of Cascade throughout (b) the poor low flow performance of the RBX (c) the crossover point around 2.25GPM where the RBX (essentially a modified whitewater) finally performs better than the standard whitewater. Most users don't have pumps like mine and so relative performance would be Cascade>Whitewater>RBX.
Look to the 1gpm numbers for 3/8" systems and to the 2GPM numbers for 1/2" loops with no other blocks.
//edit to add smaller version of graph inline