Unfortunately it's more than hardware that determines this. Hopefully they communicate with the buyers more and update the OS quickly and frequently. If Asus is smart they'll send developer phones and work with the mod community like they're doing...
Nevertheless, just skimmed read your very long post, I can assure you, my Tab S3 has good super battery life, no lagging at all and none whatsoever of any of the issues you claimed to have experienced.
OP shared the good and bad experience he ...
Full wipe new build
All works fine here
That fixed it lol. Thanks. Everything working great!
No random reboots unlike duality rom/kernel currently
Performance is better than any other rom I have tried (I've tried all on XDA)
Fingerprint is only remaining issue as it works hit or miss
Charging was slow in first kernel, 2nd kernel charg...
I moved from a 6p to XZ (F8332). Personally i think the 6P is a better phone except for battery life and heat. My XZ lasts all day and i don't even worry if i forget to charge it at night because it will last all day and almost 2 days (i work 12 h...