For just flipping the switch, no I don't think there's any implication.

For installing an unpacked extension:

- Obviously you don't have the benefit of the Chrome store checking for abuse.

- You'll need to read the manifest.json file yourself to see what permissions you're granting, because the warning popup doesn't show up when installing this way.

- There's a few attacks that unpacked extensions can do because they can spoof their extension ID, and Chrome doesn't consider it a bug. See: https://bugs.chromium.org/p/chromium/issues/detail?id=130196...