Just depends on your plans for the bike...keeper...flipper...commuter...etc.

Keepers I'll upgrade for whatever my wallet allows.

Flipper I'll only spend what I see it needs to be sell able if it's not up to snuff.

Commuter just whatever I don't really care if it gets lifted, rained on or left outside.

You only live once so why not enjoy what your riding on regardless if it's a gas piper or something first born worthy. I've tossed XTR bits onto hi ten bikes as the ride was comfy.