I've never had a problem with sign warehouse. But really its no different from a computer company, or a car dealership or anything else...They are going to charge you an hourly rate for help right? And you said it yourself, they are a big company, and by doing what they did, the helped weed out a small problem, that you got help with elsewhere so they could try to focus on bigger things I would think such as actual broken equipment or dealing with peoples whose operations are completely shut down because of problems. i mean I would be mad too, especially if it was a quick fix, but I would get over it, just because I would have to think about if I were in that situation as well.
There's a lot of people on here that complain about customers that they have, myself included, and sign warehouse probably thinks the same about us when we call for small things. Or maybe first suggestion would be to read the manual? lol I don't know, Just my 2 cents.