I was using Parker and Sons for our AC maintenance. Every time the tech arrived, he started with "let's talk about your AC". He was really salesy and pushy to the point it made me uncomfortable (how do I get rid of him?). Talking and talking and talking about why we absolutely need a new AC. Not working much. I could not take it anymore and stopped calling them.
A few months back, we stopped by Lowes and there was a rep for Day and Night. Our AC was still working but was 15 years old, so could die anytime especially at the worse time. We thought it would be a good idea to change it before the summer. The rep was nice and helpful. So we asked for an in-home estimate. Plus buying via Lowes gave us the military discount which is a significant saving.
We have been very happy with Day and Night as well as Lowes. From the estimate to the installation and the follow up visits, every one has been friendly, helpful and professional. There was a bit of an unexpected problem during the installation and they managed it very well without charging us extra. We are very happy with our new AC. To be honest, I do not see much difference on the bill. But this is because APS gouges us with taxes, surtaxes and fees. The energy production has very little impact on our total due.
We keep the same temperature as before but are overall much more comfortable in our house because the air is circulating better. And the peace of mind of not having our AC breaks down on the 4th July week-end is priceless.
To conclude, and from the experience I had so far, I would recommend Day and Night.