Does it conflict with other mods like Lspeed or govtuner? Thanks
Not yet. Mid October. I think so.
this is the link of 8.9.20 (latest) dev fastboot: http://bigota.d.miui.com/8.9.20/nitrogen_images_8.9.20_20180920.0000.00_8.1_cn_7c2f993484.tgz
For MiFlash, just google "MiFlash 2018" and download the Portable version, that's enough.
For Qualcomm ...
I too hope custom roms will help it a lot because there are already older phones that get close to mi max 3's current sot even though their battery is 1500-2k mah less but not many have a screen or size like this one which is probably everybody's ...
If anyone has problems about root, update, cwm or anything like "waiting for device...", etc... pm my inbox, I will help you if I can :)