« on: August 03, 2013, 01:33:43 AM »
I would not disagree with what has been posted. I would augment with this.
Be sure that your system is fully calibrated to obtain best results. Decide which system system you will use to do it if you can adjust AFMA.
I Got the 24-105 with my 5DIII kit and found it to be an awesome lens. I was however swayed to buy the 24-40 2.8 II based on reviews and must say it does have the edge on IQ and it is faster. Either lens however is awesome and has benefits.
Not wanting to waste your money, and knowing nothing about your current camera, and little to nothing about the 6D, my advice to you would be that if you are intent on getting the 6D anyway, get it, calibrate your lenses, optimize your technique with the new gear, then decide if you want to upgrade your lenses. You may decide that the new camera alone may be all that is needed to meet your needs.