i really want to see a performance comparison between the 580 and 600 as on camera flash using a 70-200 f2.8 at 200 to see how the 200 zoom compares to the 105 max of the 580, That would be the only reason for me to consider this flash since i already have quite a few 580s and odins for remoteHow do you like the Odin's? I would imagine you prefer them over the PW miniTT system and the Radio Poppers since you own them.
I love the odins the on screen controls are really cool and super easy to use
you can adjust power in 1/3 stop increments
and balance your A/B group power ratios really easy with the rear display
reliability and range is great too
1 button push to enable / disable HSS
its very clear from the way the odins are layed out they were designed to complement the canon flash system the best
I did look at the PW and radio poppers but for the price I think the odins take the win