HVAC Feedback appreciated -

I have been in the HVAC industry since 1979 and 2 years of Tech school before that. Here is the bottom line
1. Most equipment today is produced with the same components
2. All manufactures have baseline equipment and a higher tier equipment that is built better and is usually quieter.
3. A piece of equipment is only as good as the installation.
4. Replacing equipment is more then just swapping parts, if the entire system was not designed properly from the beginning new equipment will not help or fix past problems. The equipment needs to be sized according to the house, where its located in relation to the sun and region. If your contractor does not do a proper load calculation following Manual J standards and also makes sure for proper duct design then you are wasting your money.
5. I installed my entire system in 1995, it is a Lennox heat pump system in a tri-level house. It cools and heats correctly on all 3 levels and I have had 3 problems with it in all those years. I have had 2 run capacitors fail (one this past thursday, fixed it at 4am in the morning LOL) and had a refrigerant leak that I repaired.
6. Find a contractor that has a good reputation and be sure he does a proper evaluation on the ENTIRE system. You are going to pay anywhere from 5-8K for a complete new system.