When I first watched "Bugs", being a severe insect-phobic myself, I was pretty scared and horrified. Then, I recently watched it again and, even if it still creeps me out, especially the shower/spider scene, I must say that I found it rather watered down, in comparison to other stand-alone, Monster of the Week episodes. What it lacks is some serious tension and the original twist capable, in other episodes, like "Bloody Mary", to add an unexpected layer to the story. The plot here, on the other hand, is quite banal and straight-forward (Native Americans' massacre, curse, realization of the curse), and the end felt to me totally unrealistic and contrived: the salvaging dawn comes out like an artificial deus ex machina, and a pretty rushed one since the episode went from midnight to dawn in less the four minutes.
Fortunately, Kim Manners' touch was right there to elevate the episode from its mediocrity and the script - faulted in regards to the main storyline - did instead a great job in exploring Sam's relationship with Matt, his childhood memories and his conflictual approach to the family's legacy. This backstory further enriches Sam and Dean background, which will takes a huge step forward in the next episode, one of the very best of the season, "Home".