Difference between Z and Y-type: Bikefanclub.com

I'm replacing the cables on a set of old XTR cantis. Bike Tools Etc offers two types of dynamic link wire for canti brakes, Weinmann Y-type and Z-type. What is the difference? http://www.biketoolsetc.com/index.cgi?id=801554718567&d=single&c=Repair%20Parts&sc=Cable%20and%20Housing&tc=Straddle/Link%20Wires&item_id=WN-SH82ALG

I know that Shimano link wires have a gauge to help setup the proper angle, but is there any performance advantage of a link wire over a yoke and straddle cable?

Does this design perform better than the standard yokes?http://harriscyclery.net/site/itemdetails.cfm?ID=1251