Just a couple of additional thoughts.
I had the Yongnuo 622C flash triggers and four 580EXII and sold them when the refurbished store started carrying the 600 EX.
The Yongnuo triggers were great, but it was just one more thing to add to the set up, one more set of batteries to keep charged up and one more attachment to synchronize. And, of course, one more thing to check if something wasn't working properly. Having the radio trigger and flash in one unit is a small, but important consideration.
The 580IIs have been holding their prices pretty well and since I bought most of mine used, I was able to sell them for not much of a loss.
Two things I don't like about the 600 RT is that with the 7D (or any camera before 2012) you cannot use the camera's menu screen to set radio transmission and you are limited in the sync speed (1/125th for 7D) with radio transmission.
I have no experience with Yongnuo strobes. The reviews on the internet are mixed. Some people swear by them, but others have complained that some models are susceptible to sudden and early burnout of the flash tube. Although I don't shoot portraits for pay, I am very cognizant of the need to convey credibility and professionalism. After going through the trouble of setting up a formal portrait shoot I would be mortified if my strobe wasn't working. Of course there is no guarantee that a 600 EX won't go down, but the odds are much more slim.
Of course, I'm still bitter that Canon did not release a receiver or transceiver that would allow persons to use the 580II with the 600RT on radio control. Given the price of the ST-E3 RT there is no reason why it could not have been designed as both a transmitter and a receiver.