I need a comparison on Zune vs. Zune HD?

Hi,
I am thinking about buying either ZUNE 120gb or 16gb Zune HD
(both of them are around same price despite the fact that the capacity of HD is way less than old one)
I have looked up the reviews and stuffs but I would like to hear opinions from people who actually have one or had one
and even better comparison between the experience you had with ipod/iphone vs either one of ZUNE product
and lastly what would be the reasonable price for used ZUNE now days? I live in Windsor Canada and people sell it for $170~$200 which is good enough money for me to buy 32gb IPOD touch 3g in toronto…
well give me some ideas!!