Hands down, one of the best episodes of the first season, if not the best. Perfect for a season finale - the introduction of Butch and Cassidy, the best recurring supporting players on the show. I like them better than I like Jessie and James because they actually try to be evil and think their plans through much more thoroughly than J&J ever have. It'd be nice to see them win for once, just to prove how pathetic Jessie and James really are. Of course, for my "Intensity" fics, I used a role reversal technique - now it's Jessie and James who are the masters, and Butch and Cassidy are the losers who keep getting demoted in their feeble attempts to outdo their competition.
I didn't really care for Victreebel's introduction, though - not only did this episode lead to a running gag that quickly got stale in my eyes, but we're offered no immediate explanation as to how James got a Weepinbell prior to this episode (my theory used to be that he kept the one he stole in "A Chansey Operation"). Plus, Victreebel has a dub voice in this episode - and only in this episode. And it's nothing like his Japanese voice.