I purchased this camera 5 months ago to use in my Fashion business and also for my Photography business. I had been shooting with the Canon 7D which is a great camera. I will still shoot with the 7D for my Photography business but for my Fashion business this camera has resolved all of the lighting problems we had with interior shooting. I needed the speed of the AF and all those cross type AF points and the high fps for action shots occasionally and couldn't find anything that came close to the 7D in terms of performance before now.The Body is well built and handles well in every situation I have used this in.The Low Light capability is over the top. I have not noticed the weight at all on this camera being a problem, even with longer heavier lenses it handles well. 61-POINT AUTO FOCUS:The AF system here is identical to that in the 1Dx and is THE most sophisticated AF system EVER put in any Canon body. It is superior to that in the 1DV and all bodies before it.While most of us wanted only a 7D equivalent AF system, Canon delivered the flagship system found in the 1Dx. The AF has not missed focus for me yet.The AF accuracy, metering and noise is over the top in comparison to other cameras I have shot with and handled over the years. This camera is super fast and super sharp.I have tested the AF point in servo and one shot mode with my fastest lenses. Speed, accuracy, and consistency have been exceptional and better than anything I have used before. AF gets the job done. enter AF point and all peripheral AF points are all usable with fast primes.I am amazed with the results at 1600, after minor RAW adjustments to the noise, there is virtually no grain and the image is perfectly useable. I did test the 25600 and while I would never use this ISO in a shoot situation, I was impressed with the quality. Yes there was noise, but you're at an ISO of 25600ISO Range. This is one of the main reasons why I bought this camera. Whereas the the 5D3 is usable up to ISO 12800. (In comparison, the 7D is usable up to ISO 1600Every feature on 5D3 is an upgrade over the 5D2.BUILD QUALITY:It's hard to put my finger on exactly what changed, but the 5DIII just feels more substantial. It feels like a chopped down 1-series instead of a buffed up 10 series. The contour of the body has changed to fit your hand better. The rubber is also a new compound which is much grippier than before. The 5DIII feels much better to hold and use than the previous 5D bodies.JPEG:Out of the camera, the Canon JPEGs are phenomenal. With processing if needed they are quite remarkable.Exposure Bracketing / HDR / Stacking* The Mark III now supports 7 exposures -- A huge improvement in the software for anyone doing HDR.* The Mark III has in-camera HDR processing, which is nice (perhaps to get an idea how something looks, on the spot)* The Mark III supports in-camera image stacking, which can be used for a variety of creative and scientific effectsSD Card* Having a second slot, with the second one being SD is a very nice addition, however slows down your shooting tremendously and this is a feature I will not be using.Silent mode* It is perhaps quiet enough for you to even take a few shots in places where photography is generally frowned upon.Burst mode* 6FPS is a major improvement over the previous version. ISO:The high ISO performance of this camera is simply incredible. With the 7D I tried to limit my high ISO shooting to about 6400... I am extremely comfortable shooing up to ISO 25,600 with the 5D3. Images are still very detailed with very nice looking, fine grain. Images don't become flat looking and still have a really nice look to them. I will even shoot 51,200 without a problem, although there is a big increase of noise beyond the native ISO values. It really is impressive.he JPEG engine in this camera is staggeringly good and a solid 2 stops better at controlling noise at high ISO than the previous version.METERING: I find myself correcting with exposure compensation MUCH less now, Shooting with the two side the newfound metering accuracy of the mark III is very obvious.The new 5DIII is much improved here.WHITE BALANCE:I've noticed that while post processing I'm having to correct color less with the 5DIII files. This is very exciting, as it will save me a fair amount of time in post processing. Per usual, all of the cameras struggle under tungsten lighting. However, AWB is able to get color surprisingly close with anything that contains natural lighting.MENUS:I would strongly advise reading the manual because there are a lot of new settings and options which won't be familar to 5DII users. There are also a LOT of different ways to set up your AF system, so a little experimentation is needed. In general, the menu system is more complicated that before, but this also allows a much greater degree of customization of the camera. In that regard, the 5DIII is much closer to a 1-series than before. Take the time to learn it and set it up correctly.My next camera will definitely be the Canon EOS-1D X but for now this camera meets all of my needs and then some for my Fashion Business and my Photography business.LENS: EF 24-105mm f/4L IS USMI purchased the Canon EOS 5D Mark III 22.3 MP Full Frame CMOS with the included EF 24-105mm f/4L IS USM. I was familiar with this lens already having purchased two of them prior for two family members and using it for from time to time. I had wanted a walk around lens with IS so getting this included lens was going to be my answer for that.So far as an owner of this lens I really do not like it on my 5D camera. (personal choice) I will use it more on my 7D camera in my photography business.I am used to shooting with the EF 24-70mm f/2.8L II USM and this will be my lens that I will use the most on this camera body.