Die hard Sony user? Pre-capture from R7 to R6ii/R3 is ok. Your highly praised a1 doesn't have it.
A1 under 14bit uncompressed 50MP RAW is not reaching 20fps, 15fps roughly. Only jpeg/lossy RAW with CFA/V90 cards allows the 50MP 30fps.
It is not fast at all.
Even if you move the goal post to jpeg only, R3 is still much faster.
A1 is a overpriced with caveats and problematic White Balance algorithm. Stop praising it.
Die hard? Certainly not. Have all three systems off and on. Owned R5 for half a year, had R3 on loan from CPS a couple times. Owned Z9 twice. Have used Z8 only once. Currently shoot A1. Recently had A9III for 3 week loaner and didn't fall in love so won't be getting one permanently.
What else have I owned...how about Canon 7D, 7DII, 5DII, 5DIII, 5DSR, 5DIV, 1DIV, 1DX, 1DXII; Nikon D500, D850, Z50, Z7, Z8 (loaner), Z9; Sony A9, A9II, A7RIV, A7RV (loaner), A1, A9III (loaner).
I never said the A1 has pre-capture. I said the A9III is the only FF camera that has a good implementation and the current Canon implementation is a JOKE...as others pointed out to you after your post. That is why I said if the R5II has a good implementation of pre-capture that would be a differentiating factor from the A1/Z9/Z8 competition. If it has the implementation in current Canon camera then it is as useful as the A1's implementation...ie should just not exist at all.
Yes, A1 requires Compressed RAW to max out the FPS....as the A9 and A9II did to reach 20FPS. Only the A9III finally bucks that trend and can shoot 120FPS in all formats. This may be a deal breaker for some. For me it isn't as I've shot in Compressed on all my Sony cameras to date and have no issues with IQ for my subject matter. I also shot Canon in CRAW and shot Nikon in HE* so I never choose the Lossless RAW formats anyways as I prioritize, buffer clearing and card space over Lossless as I've never been able to see a difference in my subject matter. Others may differ in this and make choices accordingly.
R3 is 24MP, if it wasn't faster in some things compared to 50MP, I'd be very disappointed. R3 is my favourite ergonomic camera I've ever used. If Canon could do an R3S with R5II sensor in the R3 body that would be ideal...I might even buy back in (I still have a backpack full of EF Canon glass I adapt on Sony for now).
A1 price is high when compared to Z9/Z8. Compared to Canon...well hard to compare as they don't have a camera that has similar specs. R5II may be that camera and then for sure if current rumour of $3,999 is correct it will make the A1 look more overpriced then it is already appears. But we are getting 3.5 years into A1 lifespan so hard to compare as the market has changed. We will really have to wait for A1II to do a true price/feature comparison between A1II, R5II, R1 (more likely this will be compared to A9III) and Z8 or maybe future Z8II.
White balance??? no idea, I shoot a fixed K value on all my cameras so have no experience with AWB.