Not entirely on point with respect to your question, but the electric razor issue has come up before in past threads:
http://forum.calgarypuck.com/showthread.php?t=28309
http://forum.calgarypuck.com/showthread.php?t=27107
I'd love to find a good electric too. I get two, maybe three shaves out of the Mach 3 cartridge type razors. It's expensive but I wonder if thick beards would wear down an electric blade just as fast.