With ntfs you have to create a separate partition though. With btrfs you could create a subvolume and just have one big partition for both linux and windows.
This seems to run a VM rather than natively supporting linux syscalls. So termux will be more performant with its natively compiled binaries than this solution.
As for “high lead solder” - you won’t buy it in Europe. We had to learn using lead free for rework and you know what - it’s not much different, assuming you have high quality equipment.
That's bollocks. You can buy leaded solder in Europe just fine. You only need to worry about lead-free if you want to sell a commercial product.