Attention to detail, personable service and expert knowledge. I haven't done any pool caretaking in 16 years until acquiring a new house with one, not on purpose, but they have been very patient in my retraining. They also use some proprietary testing machine and computer program that spits out exactly what you need and the timing and amounts of each. No pressure to buy there either if you can find a better deal. I will go back any time I have a question and know I'm welcome. You should too.