The 'upgrade' could be one that'll make him more money. I'd stay with Mitsubishi. And I'd find a HVAC guy who specializes in Mitsubishi.

split systems?....heat pumps I assume....pay attention to heating efficiency HSPF or better COP....of course there is cost to consider...and for info, Bryant is sister company to Carrier, they are basically identical other than model level, badging, and outside cabinetry...

IMO

The Bryant Evolution is the top of the line model and pricey. Zone 5B goes down to -10F in the winter. Is this new construction and will the house have natural gas?

This is new construction. The Bryant Evolution is being proposed because it does a better job with the extreme low temps, which we do occasionally have. There is no natural gas, there is propane. With the Evolution we would get the auxiliary furnace.

Here in Maine Fujitsu is used a lot.

Bryant had better specs when we put ours in, and I wish every day that we had spent the extra money and gotten the Mitsubishi.

I wouldn't buy anything with the Bryant name on it regardless of what the spec sheet claimed. Stay with Mitsubishi or Fujitsu for mini splits.