The way the quality of a pun is judged is by the time between the punch line being delivered and the first groan. For me this was about a 5 second pun.
The lowest form of humor is the pun BUT -- Just the same I still like it!!
Oh c'mon; not the lowest, it's the highest. It's a humor form where the reader must have a certain knowledge other than the obvious the pun describes, in order to "get" the humor.