I have run into web masters, mostly newer ones and their complaint about lag had nothing to do with the hosting company at all. The complaint was about the lag from setting up the new web site and how long it took to propagate to DNS servers around the world. In short, they didn't understand "how things work" and would flame the hosting companies.

As to customer service, few hosting companies include web site programming support. This is an area that newer web masters often complain about and again all about "how things work."