Between the Utility Companies, Manufacturers and the Media, the importance of efficiency has been blown way out of proportion.
In the real world, 1 point of efficiency amounts to about $40 a year in energy savings.
Hardly worth spending hundreds or thousands more for.
14 SEER is the current minimum efficiency of equipment sold in the US.
With vastly more 14 SEER units being sold, it is and will be much easier to get parts for these units than those above 14 SEER, particularly in a pinch.
Here's a quick explanation of how things work with efficiency.
There is 'true efficiency' and 'false efficiency'.
True efficiency is when they are moving more heat using common, reasonably priced parts but larger coils.
False efficiency is when they're not moving more heat but using odd or more difficult to access motors, dual compressors, 2 speed compressors, etc., that draw less power.
These components are considerably more expensive when you have to pay out of pocket and unique parts are not commonly stocked at the wholesale house. They're not bragging about that when they're selling you a 16 SEER unit and you have no idea how long it will take to get your part, which might even be under warranty, until you're in a situation where you really need it like the middle of summer or winter.
We could tie ourselves to a particular brand or efficiency but different brands fall in and out of favor like anything else. Things change. We're not steering you to a particular brand typically but steering you toward simplicity, logic and common sense.
Though many are compelled to help 'save the planet', buying a high efficiency unit isn't going to make enough of a difference for it to be worth the additional cost or headaches.
The fact of the matter is the utility companies such as APS, for years, have been telling everyone to buy higher SEER units. Now that most have, they add a surchage on everyone's bill because they're not selling as much electricity.
They acted like they were behind solar till everyone started installing them. Then they decided they couldn't pay what they were for the electricity generated by the panels from everyone so they're going to cut the price.
We must remember the utility companies aren't here for the good of all the little children.
They are companies and coporations that act in their own best interest. It's easier on them to convince millions of people to buy high efficiency units to keep them from having to build a new generating station. They want to hold out as long as they can. But when the people start generating power back to the grid from their solar panels, they don't want to pay a fair market price and claim the people are not helping 'fund the infrastructure' thus trying to justify the lower payout.
This is all an old story. This is just about utilities, manufacturers and salesman -vs- you.
Don't be fooled into thinking you're going to save hundreds because it more than likely isn't going to happen. If it does it will only be because your old unit was drawing so much power and so out of whack that anything would have been a improvement.
Though labor warranties sound like a good idea, seldom are they what they are built up to be either. No different than extended warranties you can buy for electronics, tools, etc., it favors the mfg or shop much more than you.
One only has to imagine the scenario. It's the middle of summer. The shop has 30 calls today. 29 are money makers and then there's you with your 10 year labor warranty. Though the mfg's pay, it's nothing to write home about and they're not known for their fast payouts.
The best and smartest tech's are going to put you last and make the money first. They'll claim they're booked out several days and if you're lucky, hand you off to a new guy that doesn't quite get it all but can probably change a part. Neither is a good scenario and here in Arizona, we can't have that. When the air is out we need someone right away that's competent and is there in hours, not days.
This episode is re-ran every year all around the country. Whether it's a home warranty company, homeowners insurance or the labor warranty you bought with your new unit it doesn't matter. I wouldn't expect stellar service though you may get someone quickly on occasion if the shop makes their warranty work important, but you'll never know until you need them.
Keep it simple. Keep it reasonable.