Price tag aside I find this zoom very attractive. Sure, if you already own a 24-105 you won't have many reasons to upgrade. The optics of the 24-70/4 won't be THAT much improved. The macro function and the size-weight ratio are very interesting to use with the new 6D however. For my part I'm very interested in the macro function. For the desired 0.7x magnification you must get 2 cm close to the front-lens. Your motive will most likely be shadowed. However, 0.5x magnification will be very usable - and that's where the infamous EF 50/2.5 stops which I still use quite frequently. If optics allow reasonably sharp results I'll surely buy this lens. But I'll wait a little for prices to fall. I really hope Brian from the-digital-picture updates his review soon.