They are certified and their work is guaranteed. I'm willing to bet they have more credentials than your average "keyboard warriors."
In all honesty, probably not.
Take me...I have been hacking (the correct use of the word - coding) since 1986. I have probably more computer knowledge in my right pinkie than the script kiddies that work at Best Buy...their main M.O. is "does it boot up...no?...okay then reinstall...that'll be $100 please"
Or if your video card fails...they can unscrew one screw, slide the card out...screw it back..and let Windows find it and install it...whohoo..."that'll be $100 please". Easy money.
Today - the overwhelming number one problem is malware. In which there are several FREE programs anyone can install...the same program the Geek Squad charges you $100 to click on...no thanks.