60D + 24-70 f/2.8L II
It's a little heavy but lighter than carrying a FF and that monster of a lens around.
6D + 24-105L still beats it
Alright, I'll bite.
No, it does not! Unless you are talking about weight only (which I assume you checked somewhere) but I'm not interested in giving up my 24-70. Let me break down my argument in sections.
Sure, the 6D has better low light performance, better bokeh (given the _same_ lens) and a nicer viewfinder, just to name a few features. And these are differences that I can quote from having used the 6D next to the 60D, not from reviews. However, while we are at specs, the 6D has a lower max speed and a lower max flash sync speed than the 60D, and while the 1/250 of the 60D is not enough for a sunny day it does give you some more freedom than the 1/160 of the 6D (not a big deal, but something to mention).
Let's revisit the strengths of the 6D though (low light and bokeh). The combo you offer has a 4.0 lens, the combo I use has a 2.8 lens. This is a whole stop difference, which pretty much makes up for the 1.6 factor of the crop sensor in both light let in and bokeh. So while the 6D beats the 60D, the 6D+24-105 barely beats the 60D+24-70.
There is still the viewfinder of course, but whatever. I guess the 6D+24-105 is still better if you are doing low light landscapes with a closed down aperture for good DoF and high ISO to make up for the light, but who does that? I don't anyway and my post was about the equipment I carry.
- Return on investment:
I bought the 60D when I was on a much tighter budget, before the 6D came out, and long before I could afford the 6D anyway, since my walk-around lens was the Tamron 17-50/2.8. When the AF on that lens died, I decided to go the extra mile and buy a lens (24-70/2.8L II) that not only is far superior, but also enables me one day to switch to a FF body. At the time of purchase I spent $1800 for it (after rebates and whatnot). The combo you are suggesting is still about $700 higher (and that's if you buy gray market on ebay) and back then it was a good $1K higher.
- The limiting factor:
I view photography like sport car racing. If all you can drive is a Suburban, you don't need to move up from your Porsche to a Ferrari, you need to learn how to drive better. When you can fully control your Porsche and you miss some races because it can't deliver, then move up to the Ferrari. I guess I'm not the photographer you are, or don't do the type of photography you do (low light landscapes?) because I'm barely every limited by my camera. I've been limited by lack of sufficient control of external lights a lot, that's why my latest purchases have been speedlights, modifiers, remote triggers and lately a witstro 360. I've missed a lot of shots, and screwed up others, but I honestly can't think of a single shot that I missed because the 60D was not enough camera.
- The bottom line:
I shot those three over the holidays. Can you tell that they are done with a four year old underspeced camera?
Yes, we may have different expectations for the gear we use, nothing wrong with that. I don't really worry about that 1/160sec flash sync (it's just a weird number and it's not even there when the flash isn't mounted) and the max shutter speed. When I had my 7D, the only 1/8000 pictures I took are the ones I tried if it actually works. For me, too much light isn't the problem
and (if something) there is ISO 50 nowadays (not sure if 60D got that one).
It doesn't really matter if I can tell the difference looking at these beautiful images you took. That's a common misconception, the image itself is not enough data to judge the tool, I can't know the actual distances, sizes or proportions used in a 2D composition, not to mention cropping. Gear matters mostly when you are shooting the picture and which set gives you more potential for the money. With 6D+24-105L it is possible to reproduce pretty much any image you can shoot with a 60D+24-70L'II, but not vice versa. 24-70L'II on crop isn't as wide, f/2.8 translates into f/4.5 not f/4 (not a big difference, but still, for the price and fair comparison 24-105L at f/4.5 is just as good or even better optically) and then there is weight, filter size, no IS, diffraction and stuff (I'm not sure and correct me if I'm wrong, but 6D+24-105L at f/11 may give you better contrast than 60D+24-70L'II at f/8).
Looking at the current prices I see that 6D+24-105L combo goes for $2400 new at B&H (or $2100 after rebate) and the 24-70L'II alone costs $2000 (or $1850 after rebate). $250 (the difference) for the body?
Finally, there is Sigma 18-35/1.8 Art ($800 new), which IMHO makes a lot more sense for a crop camera.
However, the most important thing is the joy of using whatever toy you've got and the experience you learn with it.