I have been considering selling my setup
24-70 2.8 mkii
70-200 2.8 is mkii
600 exrt speedlite
To get a 6d
24-70 f4 is
Newer speedlite 430ex ii replacement
I just spent thousands of dollars this year and have hardly used the gear. When I do its for candids or vacations. I wonder if I am wasting the money and should sell it to downgrade to something more enthusiast level and cheaper. Also it's just so much to lug around. Just not sure and wanted some opinions.
If you want to stay SLR, you may want to wait for the 6D w/ 24-70 IS kit to arrive and prices to have a rebate.
Right now, you'd probably get $2,300 for the 5D3, and pay $1,899 for the 6D body. If you could get a good deal with a 6D/24-70IS kit on rebate, it may be worth the change.
For the lenses, you could even sell those now, and make not bad money. The 24-105mm used is sub $800, you could probably sell one in 6 months to a year for a negligible drop from there. I'd seriously consider doing this, and then downgrading the 600RT for a used 430EX. The 70-200 f/2.8 II is also going to net you some cash when downgrading to the 70-300L.
The CF cards are likely going to be something of a write off on the used market.
All in all, I'd consider selling the lenses and flash, but keep the body until you can get a cheaper 6D & 24-70IS kit, if you are set on the 24-70.