He is correct if you leave the components out in the elements for some time. If they were stores with caps on them, it's OK.
He is stating this because critters, dirt and corrosion all could assist in deteriorating the inside of the components.
I would recommend replacing all fo the hoses if the system has been apart for some time (more than a few weeks).
One thing you could do to save the evap and condensor is to install them and draw down the system with a vacuum pump. If that vacuum holds overnight, then go, else you need to find the leak.
He is stating this because critters, dirt and corrosion all could assist in deteriorating the inside of the components.
I would recommend replacing all fo the hoses if the system has been apart for some time (more than a few weeks).
One thing you could do to save the evap and condensor is to install them and draw down the system with a vacuum pump. If that vacuum holds overnight, then go, else you need to find the leak.