As someone that has installed HVAC equipment for over 25 years, I would advise worrying more about the actual guys installing the equipment. Most of the equipment out nowadays are all pretty much the same. Some equipment will certainly be quieter than others so if that's important then specifically ask about that. Ask A lot about the guys installing it. I wouldn't get excited about how much school they have I would only be concerned about actual experience. If the lead guy doesn't have a minimum of 5 years I wouldn't have them on my job. Having an apprentice there helping is normal but there should be plenty of experience with the other guy.
Most residential installations can be fairly easy and even a handy homeowner can do most of it. The actual A/C end of the job is where you absolutely want the time to be taken to do it correctly. That is where the biggest service cost would come in the future. I put high efficiency equipment in my house because I get it for cost and maintain it myself. I wouldn't pay for it to be installed unless you are replacing a high efficiency furnace That is already there. The simpler the system the easier to install and the less to go wrong. Don't let the salesman sell you on features that NO ONE ever uses. Some of the equipment out there now can do some incredible stuff but I have yet to see a normal homeowner ever benefit for those features.
