You can have both. I hear dual booting has gotten a lot safer lately, but I prefer to keep windows contained in a virtual machine, which has the added benefit of snapshots for when windows update eventually does something I didn’t approve. Maintaining windows is so much less stressful when it’s not running on bare metal.
If you’re very worried about performance, then you probably will need new hardware by the time you need to make this decision anyway. I’ve never actually purchased windows directly; I just find an upgrade that bundles an OEM key if I need a new Windows.