I don't know if it's common but I have a 98.5 Mystique V6 with 111,000 miles and my AC seems to be as cold as when I first drove it home from the dealer. Now that I think of it that was at the end of the month of November and about 35F degrees but you know what I mean.
The only time I had any trouble was earlier this summer when I had it apart doing some engine work and I pedaled to work for two weeks straight. The first time I drove the car the AC wasn't cold at all and I figured something had rusted and seized up that I would have to replace. The next day it was back to normal.
