Research in Motion mounted an impressive rally over the past few months in anticipation to the release of its new BlackBerry 10 smartphones, yet investors may havebeen irrationally exuberant. Recent channel checks by Canaccord Genuity suggest sales have dramatically underperformed previous estimates, mainly because of supply constraints and limited support from carriers. While the product may look good, it will be difficult for RIM’s Z10s and Q10s to compete with a host of new Android and Window phones, and possibly a new iPhone expected in the first half of 2013, according to Canaccord’s analysts.