I bought an E3 wireless computer at Performance a month ago. I did not know at the time it was a Performance brand (that may have affected my decision). It all seemed to work fine. Then I was noticing variability in the distance on a known route. Yesterday I rode a century. The computer added two miles while I went into a convenience store. At the next stop I leaned the bike against the building and the bike registers 76mph and the mileage is just whizzing along like anything. WHen I moved further away from the building it stopped. That evening I took it back to Performance and got a Cateye Mity 8 (wired). The manager tried to write it off as "all wireless will have this problem". My Cateye Strada wireless has never seen this. ANyone else have an E3 and had problems? What about other wireless systems?