Depends what you are trying to accomplish.
A "hard reset" through ##786 and privacy->reset doesn't restore the /system partition back to original. You might for example want everything back to stock with no remnants if you were to return a phone to Sprint and you didn't want them saying you did something to your phone.
Keep in mind after you apply the VC OTA update (not recommended for others to use the OTA update), you won't be able to root again and go clean stuff up, so if that is something you want to do, make sure you do it ahead of time, and don't depend on a "hard reset" clearing everything out.
However it is up to you. If you have something that is very close to stock (or stock just rooted), you can apply the VC OTA update and have a VC that is unrootable (which you seem to be ok with) Again, personally I would use the LG Update tool, so if you change your mind later on, you still have the option to root, but I don't know your circumstances.