I want to buy a Keystone, just for use with Metamask and to store altcoins, like ETH, Sol, USDT, USDC.
Considering that they only communicate through QR codes, and the firmware of Keystone and the Metamask app are both open-source, and come from different companies, wouldn't that make it more secure?
It would make it safer to use that way, but I just never like Metamask wallet and I don't care much about ethereum and all it's tokens, but Rabby.io wallet is much better alternative for metamask.
Watch out for Keystone wallet battery, you have to charge it on regular basis or it could stop working and die, this is the weak spot of new Keystone 3 devices, and it's not easy to replace them.