I agree that the variable speed units offer some advantages and they are most likely the wave of the future. My comments are strictly related to the current residential market, the cost, and the repairability of the different systems. As of today, I would prefer the "tried and true" approach. I'll let someone else experiment with the new-fangled equipment.

Variable speed units have been around for decades. In most cases they will last much longer than standard induction motors and provide better energy efficiency and temperature control.

https://www.achrnews.com/ext/resourc...hite-Paper.pdf
Variable Speed’s Impact on HVAC | 2017-02-06 | ACHRNEWS | ACHR News
The Scoop on Variable Speed Motors - Lee's Air, Plumbing and Heating
https://www.hvac-talk.com/threads/va...ility.2219493/
VSD vs fixed speed - Atlas Copco USA

I know they are not new, but they have not sold well in the residential market in this area. My only point is that, when I replace an essential item in my house, I tend to go with the standard product being used in the community. That way I know I can get it serviced or repaired easily. Obviously, the standard compressor used in The Villages is a single stage compressor. The Villages builder has installed thousands of them. This would apply to roofing, a water heater, and other construction items. But I don't have an issue if someone wants to buy a variable speed compressor.

If your home has very good insulation, I believe the best option is a single stage compressor with a soft starter. I am very pleased with mine. It provides another layer of protection from electrical faults and the reduced inrush current will significantly extend the life of the compressor.

The target market for these devices is RV's since they have concerns of tripping circuits if the starting current exceeds peak limits.

You should have your contactors and capacitors replaced at least every 10 years. It only takes minutes.

I have variable speed and it is the most comfortable unit I ever owned. You never notice cold air blowing and then it going off and being hot just a comfortable even temperature.

I don't mean to disagree with you, everyone is entitled to their opinion, but the statement that "I know they are not new, but they have not sold well in the residential market in this area.", I don't think that is true any more. Even if you live in an older area where everyone's original HVAC system is ready to be replaced, generally, you don't see the change out in mass so it's hard to tell who's replacing with which system and it's hard to find statistical information on that point. In talking to the sales person from my HVAC company, again unscientific, he's telling me more people are now upgrading to the newer variable speed inverter systems since the cost, right now, is close enough to a single stage system and people are more aware of the technology. I have friends who recently purchased in Middleton and opted for the Variable speed system which is now an option offered by the developer. In principal, I understand your comments and feelings on the topic but there is only one statistic which supports your claim and I'm not sure how relevant it is today. But thanks for the alternate point of view.

I also like these soft start units and I know if you have a generator you need to install one of these devices but I also think it may void your warranty. So, if you install one you really need to check with your HVAC company or better call the manufacturer.

But, a single stage system with one of these devices will make your system last longer but not give you the same benefits of a variable speed system.