i've used the Eichmans on a pair of speaker cables i demoed. baring in mind this was a well used pair of demo cables, the eichmans were great. i really like the low mass philosophy employed in all there connectors and already use their silver bullets on my interconnects. admittedly they were on a completely different cable, and i'm sure that the cable played most of the part in this, but the sound was much better with this cable than my stock ones. so if the plugs were a degrading factor, it clearly didn't demonstrate that.
i will say that they can be bent and can get pretty beat up looking when used heavily, but then how often do you really plug and unplug cables? if you just attach them and then don't screw about with them much, they are imo great. wbt and the rest, seem like expensive audio jewellery in comparison, the hi fi equivalent of a heavy gold chain and medallion....