If you don't fill up 128GB, the 6/128 is a great choice. Unfortunately I have a 55GB music library
swathes of which prevent me from switching to streaming services. Also I read some stuff on annoying limitations on SD card access for Xiaomi phones so I didn't want to deal with that.
I'm sure SD860 (X3 Pro), Dimensity 1100 (X3 GT), Dimensity 1200 (F3 GT) and SD870 (F3) would all be a massive step up from the Meizu. 224EUR is definitely a bit cheaper than $385CAD, seems like a good deal, especially if Xiaomi has an official presence in your country so you don't have to buy grey market like me.
I feel you on the size. For the first few months, my OP6T really was too big even for my huge hands. I got used to it I guess. But the X3 Pro and F3 are 0.2" even bigger, so we'll see.
@Mussels is your SN850 on the CPU slot or one of the chipset slots? I'm rather convinced that WD's controller architecture has difficulties playing nicely with any of AMD's chipsets. Remember that whole ordeal about that dude's SN850 getting shit performance on the X570 ITX/TB3 because the M.2 on that board is hooked up to the chipset? And then there's my own original SN750 and new RMA SN750, both of which have fits when connected to the chipset on my Unify-X, even though my SX8200 has done just fine on the chipset slot this whole time. I ended up putting it in the CPU slot and it runs like a top.