That's a fair question. The Kaiweets meters are generally solid value for the money and will be perfectly adequate for most hobby builds and basic Arduino work, which mostly involves 5V or 3.3V logic. You can rely on it to troubleshoot most issues. For true small signal work where you're dealing with microvolts or very sensitive analog circuits, a budget meter's limitations, like slightly less accuracy on the lowest ranges or higher input impedance, might be noticeable. However, it's still a great tool for getting started! Save your money for now. If you eventually move into professional audio or RF design, you can always upgrade to a Fluke or Keysight later!