I think these guys are professional BUT my experience was not good and I would not call these folks back.
I had a room in the house that was not getting cooled properly. Alaska came out and concluded the only solution was a new $9k system or a $4k zone system.
They felt a duct booster fan - a solution I had read about on the net would not solve my problem. Well I went w a competitor who agreed w me. A duct booster fan and window tint was a simple low cost effective solution. Still not sure why these guys missed it.