Sony has a plethora of APSC cameras. I just thought that I would put down my initial thoughts on the A6600...
I have decided to sell my A6500 and have purchased the A6600 in a kit with several really nice accessories from Adorama. IMO, the $200 price reduction of the A6600 makes the camera more competitive. Usually when a retailer packages accessories with a camera these accessories are crap. This is not the case with A6600 Adorama package from Adorama https://www.adorama.com/isoa6600d.html. This is really a free offer since the cost of the camera with this package is the same as the cost of the package alone However, I plan on selling the flash that was included in this package since I already own two identical units.
BTW: Adorama has an upgraded package that I probably would have purchased had I seem it. It includse a 128GB SD card vs. 64GB, two extra batteries vs. one, dual charger vs. single charger, Peak Design SlideLite strap and Flashpoint Wave Commander intervalometer for an extra $50 USD.
First of all - I love my A6400 and plan to keep shooting with it in tandem with the new A6600 which has just arrived. I will often photograph over a hundred dogs a year for Maltese Rescue California and the Animal Eye-AF of both these cameras is nothing short of outstanding. The small form factor of each of these cameras combined with Animal Eye-AF makes it easier to shoot one handed while I am offering the dog treats with the other hand.
Here are a few parameters of the A6600 which I really love. I have numbered them in their importance to me personally in my style of shooting. Other photographers would certainly list them in a different order.
1. LARGER GRIP... The grip of the A6600 is significantly larger (actually it should be described as "deeper") than any other A6xxx series camera in order to fit the Z battery. The larger grip is a lot more comfortable to hold than the smaller grips of the previous A6xxx cameras. This is especially beneficial when shooting one handed and/or when shooting with a slightly larger lens such as the Tamron 28-75mm f/2.8 or the Sony 70-350mm f/4.5-5.6.
2. ISO 50... This has not been addressed by any reviewer that I have noticed. I really like the ISO 50 capability of the A6600. The top shutter speed of any A6xxx camera is 1/4000 second which sometimes is too slow when I want to shoot wide open with a very fast lens in bright conditions using ISO 100 which is the lowest ISO of previous A6xxx cameras.. I have often wished that I had the advantage of 1/8000 second shutter speed. However, the ISO 50 capability should often allow decent exposure wide open at 1/4000 second. This ISO also makes using a very slow shutter speed sometimes feasible without an ND filter.
3. EASIER REMOVAL REPLACEMENT OF SD CARD... The larger Z battery allows space for positioning the SD card slot in a location that makes it easier to remove and replace the card.
4. IBIS... Since I don't shoot video, the lack of IBIS in the A6400 and the IBIS capability of the A6600, is not a deal breaker for me. However, it is nice to have when I am shooting with non-OSS lenses or when I am shooting hand-held with the 70-350mm f/4.5-5.6 G OSS lens. I have not yet ascertained just how slow I can shoot using the IBIS/OSS combination with the A6600 but, in early trials it seems that I can effectively hand hold at slower shutter speeds than with the OSS lens and a non-IBIS A6400.
5. GREATER BATTERY CAPACITY... Again, I am not a video shooter so the relatively low capacity of the FW50 batteries of the previous A6xxx series cameras has not impacted on my shooting to any great degree. I always carry extra batteries and my Meike battery grip for the A6400 will provide just about equal battery capacity. This grip will also extend the height of my grip on the camera but, will not impact the depth of my grip. Given the size of my hand (I wear extra large USA size gloves), my grip on the A6600 is basically with my middle and ring fingers around the grip, my index finger operating the shutter button and my small finger curled under the camera body. This is to me a very comfortable and secure grip. I am thinking that a hand strap would even increase the comfort somewhat; since with a hand strap some of the camera weight would be supported by the back of my hand...
6. TWO ADDITIONAL CUSTOM BUTTONS... The C3 and C4 custom buttons allow even more customization of the A6600.