Now for PFB, I haven't seen all that many as my PBS stations basically only showed it for a bit when it first aired and then it never returned to my area.
I definitely saw the season 3 episode "Ciao, Buster" and the season 1 episode "Best Friends." However I know that I saw multiple other episodes of the show, just can't quite pinpoint off hand exactly which.
Several of the PFB episodes are on PBS' site.