I don't need my data offline when it doesn't have to be. You don't need extra drives sitting around. When one fails, you buy one, Amazon can have it over in a

I don't need my data offline when it doesn't have to be. You don't need extra drives sitting around. When one fails, you buy one, Amazon can have it over in a day, or local shops. If it's not realistic for that, having one spare isn't a bad thing. If you replace with a larger capacity drive, the existing raid only uses the same size to keep the raid. Depending on the drives you are using, SMR technology can take much much longer to rebuild a raid than CMR. Self-storage should be like a cloud - people need to rely on it like a cloud provider. Hot swap is a negligible cost over the 5-10 years you keep a NAS. Hot swap chassis whether it's one you buy or a Synology/QNAP, etc is the way to go. Hot swap used to cost a ton, it's considerably come down market. Storage is like a home appliance for me, just because I could build a stove doesn't mean I should. I've spent enough time swapping hard drives manually and powering off gear to know that I don't care for it if I don't have to anymore.