Agreed, my vote is for IDR or POW-R, but don't just switch them on, try out different settings when dithereing each project or song - the differences in character are not easily spotted at first, but go for what "feels" best and you should be in the ballpark. (Note that in IDR there is a setting where the dither is of, you don't wanna do this.) My personal preference right now are the POW-R dithers.
I used the UV22 dither for a while about two years ago. At first I liked what I heard, but I got tired of it's sound - it has one.
BTW, can someone explain what on earth the digital/analog switch on the L1/IDR is for?? Sure, the settings sound different but I don't know what they do - anyone? (I'm looking for a tech explanation)
Ben