I actually have both the Iriver IHP 120 and the IPOD (forgot what generation but i know it has no dock adapter)
anyway, they are both 20 gig, and i actually prefer the Iriver over the Ipod just because the battery life on it is a little better
and i don't always have to carry around an adapter.
Also the Iriver 120 can be plug in with a typical USB cable. My Ipod only has firewire so that can be a bit of a problem with some older computers.
I don't need all the functions of the Iriver, but I'm definitely not going to be staring at my Ipod all day long anywayz, so why do i care if the Iriver is not as sleek as the Ipod.
Just my 2 cents.