I also got the WR-5 when it was on the crazy $64 sale on Amazon last week. Love it so far but am also experiencing the weird date set problem. Whenever I try to set it to January 2013, it works but then a few hours later, it reverts to October 2012. Really frustrating.
I don't know if the software is bad or it's just my unit and yours. (some Amazon reviewers also have noted the problem). Maybe I'll ask Amazon to send a replacement unit to see if the problem occurs on that one as well.
By the way, I set the clock/date manually, rather than use the RDS CT method-- maybe I should try that instead?