Hi Steve, have you seen Matt Grangers latest tests using F-mount lenses on the Nikon Z9 using the latest adapter?In all likelihood, you'll end up just using the Z9. I think I echo the experiences of many others when I say I intended to use both DSLRs and mirrorless, but once you start using a really high quality mirrorless camera, you just don't pick up the DSLRs anymore. I thought I'd use both for much longer, but I haven't used a DSLR in six months and even then it was only for 30 minutes or so because I didn't have the correct lens for my mirrorless gear. I also think that you'll discover that over the next year or so the market will continue to flood with used DSLRs and that will drive down their used value, so the sooner you let go, the better. (I easily lost $1000 on what I could have got for my D6 by waiting too long to sell).
The results are interesting & if accurate could give people the option of keeping their beloved F-mount primes & use them on a mirrorless body with no loss of quality.
Would be interested to hear your thoughts.