Best DAC for Sonos


I was thinking of purchasing either a: PS Audio Link iii, Benchmark DAC1, Cambridge DACMagic or Musical Fedility V-DAC. Does anyone have thoughts on what might be the best to go between my Sonos and Krell preamp? Are there others that might be better?

Thanks in advance.
slinker001
I should add that I had the Cullen mod (now done by W4S) done to my ZP-90 and it made a noticeable difference. Was it worth the money? It's a lot, more than the Sonos itself, but I love the Sonos controlled via my iPad. I wish it were cheaper, but it definitely made a difference and if your Sonos is your primary source, I strongly recommend it after being a doubter for a while...difference was immediately noticeable.
I just scored a Dac Magic and I think it sounds amazing drivin by a Squeezebox Touch and an old Marantz CD changer's digital out (I use the groovy balanced outs into the preamp). I mean amazing...but since it's so cheap you maybe should get something more expensive so audio freaks don't scoff at you. I heard a friend's Sonos into a Wyred4sound DAC2 and it's nice and has that higher cost one wants in a component.
Beresford is cheap in cost and plays better than a lot of the DACs mentioned. It probably plays in the 800-900 dollar range but only costs 250.