I have a joe blow and a specialized. The specialized has the better pump head of the two although I sometimes found that with a completely empty tube it didn't always work without fiddling. The joe blow wouldn't always work when just topping off a tire unless you released a little air. I then swapped the head on the Joe Blow for a KNCN head - which is now the best pump I have ever used by a long shot.

Between the two without swapping the head, I would get the specialized in a heart beat. I didn't swap the head on the specialized since it just works pretty well, all the time.

I don't like having the screw the pump head onto the valve, so never went for some of the classic "best" pumps.