Primarily, Diablo Solar Services were very business-like. They came to look over my solar at my Concord house; both pool filters, and the solar and electric system. The service people as well as the work done were professional. They were on time and on budget--exactly what one would hope to have with a contractor which is rare! I’ve had them three other times in the past. As long as they do a good job and their prices are competitive, I’m certainly going to go with Diablo Solar Services!