Is it recommended to replace evaporator core when replacing heater core? on 1999 Jeep Grand Cherokee

I am having my heater core replaced. One mechanic recommended having evaporator core replaced, too, since he will already be in that part of the engine. He said they often go bad within a few months of the heater core.
What are your thoughts and recommendations?

Asked by for the 1999 Jeep Grand Cherokee
I have generally not heard of replace the evaporator core along with the heater core. If the heater box must be removed (that appears to be the case with your 1999 Jeep Grand Cherokee) to perform both repairs, that would be the only time I would even think about doing it. There is some piece of mind in the fact that if both parts are replaced while the heater box is out chances are it will not need to be done again.
Thanks for you input. I heard it is rare that the heater core go out on a Jeep Grand Cherokee. It is supposed to last the life of the vehicle. I realize it is quite a job to take it out and it would bring peace of mind to have both done at the same time. Just don't want to spend unnecessary money. It gives me something to think about.
1 more answer
Yes , it is a good idea. The labor to remove the heater core, is a lot of time.
The evaporator is in the same location.