Is this economically viable or just a show-off? Because considering the skilled labour and equipment, I’m not sure it’d be much cheaper than the $500 upgrade.
It's not economically viable because the NANDs come from donor systems. Apple prevents the NAND oem from selling to anyone but them. It's part of their anti right to repair strategy.
I don't have an answer but you can upgrade your existing phone you already bought using that method/service. Otherwise cost of official "upgrade" is $500 and a new iphone
