I see two other reviews and both very negative. I would like to invite both of those reviewers to run a small business of their own sometime. Do they charge more then Amazon or the Big Box stores? Yes. Do they make a profit on service and parts? Yes. The fact the items they work on tend to be low priced makes the economy of scale seem like you're getting a bad deal.
I say you are not. The fact they stock the parts, over the years have honed their abilities and can do a competent repair in a short amount of time is a good business model for them and a valuable service to the community. In this ever disposable society I for one will use a business such as Shav-Tronics whenever possible.
So bad reviewers, next time you take one of your vehicles in for a service make sure and bitch at them just as you have with this business owner.