Sony A6400 or A6600?

Hi, I use the A9 & 200-600 lens predominately for my bird/wildlife photography, I was going to buy the 1.4 extender to use with the 70-200 F4 on the A9 but bought an A6000 instead as that still gives the F4 with the 1.5 crop sensor factor and not having to put on take off an extender, anyway I am thinking of selling the A6000 and buying the A6400 or A6600 but only to use with the 70-200 F4. So the question is do I go for A6400 or A6600?
Thanks.
Russ.
Thanks.
Russ.

The A6600 is also the only Sony APS-C body that uses the more powerful FZ100 battery, which I think is the same as in your A9. That might be of benefit to you? However, given how expensive the A6600 is, I'd also look at a used A7RIII - much higher resolution and you can crop the image in post to get equivalent framing. There are plenty available on MPB and other sites in the £1,300-£1,600 range.

I have an A6600 and very pleased with it. I have had it for 12 months now. At the time, I looked at the reviews and the A6600 was the best spec from the 6000 series but it was the newest. While I usually carry a spare Battery, I have not yet needed it yet. I was at Slimbridge WWT yesterday and captured 639 frames and there was still 50% battery power left. I cannot comment on price as it was not an issue for me given I have a Canon 5D4 and several lenses which at second hand value would have easily paid for the A6600 and its lenses but I did not sell the Canon equipment as I wished to retain it for now.
Dave
Dave

Defiantly like the idea that the A6600 uses the same batteries as the A9 but the suggestion of the A7RIII I will look into, I was tempted to go down the A7R IV route with the 60+ MP's but not so good as the A9 for BIF or focus response and hands up THE PRICE compared to the A6600
Thankyou for the replies. Russ.

Thankyou for the replies. Russ.

There are many differences between the A6600 and A6500 so worth checking before deciding; a simple google will tell you.
6600 Grip is larger
6600 battery larger
6600 tilting screen includes 180 degrees
6600 focusing better and faster
6600 eye detection includes animals
6600 larger ISO range
6600 unlimited video recording time
6600 HDR video
6600 Headphone output
6600 no built in flash but 6500 has. I considered this to be an advantage as I would never use a built in flash as it is wrongly positioned
You need to consider the various features and relevance to your photography. Though bird photography is not my main subject (I do everything), I was very impressed with the A6600 on my recent visit to Slimbridge particularly for birds in flight.
Dave
6600 Grip is larger
6600 battery larger
6600 tilting screen includes 180 degrees
6600 focusing better and faster
6600 eye detection includes animals
6600 larger ISO range
6600 unlimited video recording time
6600 HDR video
6600 Headphone output
6600 no built in flash but 6500 has. I considered this to be an advantage as I would never use a built in flash as it is wrongly positioned
You need to consider the various features and relevance to your photography. Though bird photography is not my main subject (I do everything), I was very impressed with the A6600 on my recent visit to Slimbridge particularly for birds in flight.
Dave