Siemer Heating & Cooling has, in the past, always been wonderful. They're consistent, reliable, and generally a pleasure to work with. For the most part, they deserve perfect ratings, because they're professional and dependable and I don't tend to have any problems with them. The only reason I'm not giving them five stars, this time, is that most recently, when a technician came out for my biannual maintenance check, and replaced a filter for me, he didn't have his receipt book with him. He assured me he'd mail me the receipt, but I haven't received it, yet, so I'm still waiting for that. Other than this, they've been good. I wouldn't have a problem recommending them to others. Thanks, Siemer!