hello, whammy pedal?
as far as i know none of the whammy pedals can properly handle more than one note, although the bizarre squawking noise they make when you try is kinda cool :lol: ! i have an xp1oo whammy-wah, which is pretty good. i tried an original whammy and couldn't really see much difference, except the xp100 adds some decent wah models. the original whammy is ridiculously expensive these days and the reissue isn't exactly cheap, but you might find an xp100 for a good price.
i have an electro-harmonix POG as well, it's nothing like a whammy. yes, you can play chords, which is great. it doubles the notes an octave down, an octave up and two octaves up, also adds detuned versions of both +1 and +2, for a chorusy 12 string effect. it doesn't have any kind of expression pedal so you can't do dive bombs and it doesn't do harmonising, it does octaves. it is, however, brilliant! once you've heard your guitar sounding like a hammond organ, you'll smile for at least 12 minutes :P !