But I am about to buy a new HW wallet. What do you guys think is the best option right now? The software should be open source and the memory should be enough to manage at least 10 coins. Is Ledger Nano X a good option?
My Nano S works just fine for several years, but I would never upgrade it to the Nano X. I am against the idea of Bluetooth, a battery (especially following the fiasco with all those battery hardware problems that the Nano X had), and I don't need storage space for 100 coins. I wouldn't be able to write down 100 coins to save my life. And neither could those who say that is the reason for their purchase of a Nano X.
However, it would be nice if the Nano S could at least support 4-5 installed coins at once. But it doesn't.
Based on what is available right now. I would probably take one of the two Trezor HWs. Just make sure you extend your seed with a long and secure passphrase. But don't expect to get one of those until February either, unless you are purchasing one from an official reseller who still has some.