I have used Blue Marlin for about nine months since buying new house with pool. Frankly, they won my business by default of being the only company that responded to the 5-6 inquiries I submitted on other company's websites.
John is very knowledgable and helpful in helping a newbie learn how to use his pool. Their prices are so good, that I actually worry that they aren't charging enough to stay in business. They obviously understand the importance of great customer service.