Best approach to modify a .VMX file

OK, so I know a .vmx file can be directly edited (power down the VM, remove from the vCenter registry, edit and then re-register).

You can also use the PowerCLI to script it... BUT... do you also have to perform the same steps (as above, i.e.; remove, edit re-register)?

Finally, is there another approach, for instance, a method using the vSphere Client vCenter GUI to selectively add/subtract line items from the .vmx file and/or change their values from (for example) FALSE to TRUE?

Thanks in advance for any advice you can give.