Hi All,
I'm getting nearer to making a purchase decision around my next EOS body. Obviously the 5D Mark III is the flavour of the month, and I've tried it out a couple of times at camera shops and been very impressed. However, the price is very high (US$4200) for this body in New Zealand, so I'm considering the following used alternatives:
1DS Mark III - the previous 'big daddy' of the range. A mint condition used 1dsIII is a couple of hundred dollars cheaper than a new 5D Mark III. It's only 1fps slower than the 5D, but has better shutter response and weather sealing. Does its image quality hold up well against the 5D? And could you use its 5fps for sports/action photography, within reason?
Wow, I didn't realize the 1DsIII's had plummeted so much in price. Looks like they're going for $3.500 to $4,000 on ebay. Very tempting

I've only taken my 5DIII on one real shoot so far, and overall it's a great camera. Image quality wise, however, it's not much of a jump from the 5DII, which was pretty much dead even with the 1DsIII. For the sake of your comparison, ISO performance aside, the IQ between the 5DIII and 1DsIII should be very close. On the other hand, if high ISO shooting is a priority, the 5DIII wins hands down.
Unless you're making money as a sports photographer, I'd say 5 FPS is plenty for some mild action. I was at an autocross a few weeks ago with a 1DIIn, and at times it's 8 FPS was a bit much.
1D Mark III - For the price of a new 5D Mark III, I could buy TWO of these second hand, plus a nice quality prime. Obviously it's a crop body, but with the right lenses I'm sure it wouldn't matter too much, would it? How high would you say you can crank up the ISO before it becomes unusable? I'm used to being limited to ISO800 on my 40D, and wouldn't mind having access to another stop.
While the 5DIII is a huge improvement in terms of build quality, reduced shutter lag, and ergonomics, it's still not a 1-series body. Even compared to my 7-year-old 1DII, the 5DIII isn't quite as snappy or responsive. The 5DIII is no slouch, but the AF acquisition and responsiveness of the 1DII is just blazing fast. I'd imagine that the 1DIII is at least as fast. The burst rate on both the 5DIII and 7D can slow down in difficult lighting or focus conditions, which can get very annoying.
I'm a big fan of the APS-H sensor and was sad to see it go. I very much preferred the IQ of the APS-H sensor over any APS-C body, and you still get some extra reach compared to a FF body.
5D Mark II + 7D - This is another option that's being thrown around a lot these days. 5D for resolution and image quality, and the 7D for action. I could buy both bodies brand new and still have change left over, compared with the price of the 5D Mark III. Has anyone opted for this combination over the 5D Mark III?
I considered getting a 7D to supplement my 5DC several years ago, but as much as I wanted to like the 7D, I couldn't. I rented it for a few days, and overall, it's a great camera, but I just didn't like the look of its files. I loved everything about it except the IQ.
I shoot a wide range of subjects, from sports to landscapes to families and weddings. Good weatherproofing is important to me (been caught in the rain too many times) - video is not. It's quite possible that the only camera that will suit my needs is the 5D Mark III (I can't afford the 1DX), but I'm interested to hear whether any of these others might be worthy options.
Thanks
What are you currently shooting with? You can't go wrong with any of the options you presented. I suppose budget, and how your prioritize factors such as resolution, ISO, and handling will be the determining factors.