Call me crazy, but up until THE TIME OF THEIR LIVES, I've always pegged most A&C films to be interchangeable. Just a bunch of funny routines thrown in with romantic sub plots and musical numbers. Fun movies, but none I'd consider a classic. I will say the plumbing stuff of IN SOCIETY stands out as does 7 X 13 = 28 with Shemp in IN THE NAVY, but overall, I like the mid - later stuff better. THE TIME OF THEIR LIVES is a classic and I even like LITTLE GIANT, Costello's attempt at Chaplin like pathos. Most people knock that one, but I enjoy it.
Of course, the monster rally films rock the casbah. As I'm and A & C and Universal Horror fan, it's impossible for me not to like them. AFRICA SCREAMS with Shemp and Besser is also great and the TV show is mandatory Bud and Lou.