I had the same experience using a single hard drive. Two, ime, works flawlessly. Though i haven’t added windows boot to grub so i need to use BIOS to load windows, which is easy enough i haven’t bothered with grub. Your experience may vary based on BIOS.
I just get bothered that even on very modern tech my CPU is under load even when idle in Win11 such that the fan is spooling up. I’m convinced they’re sneaking distributed AI compute into personal PCs. Doesn’t happen on my Linux install.