Until I got my Forester, I could have cared less, even thought it was a bit of a negative but got at with the Touring package as it had stuff I really wanted.
Now, 2 1/2 years later, I love it. The sun shade is hardly ever closed, especially in winter as it seems to help heat the cabin. I like the bright, airy feel you get with it. And the ventilation when you need it is nice.
But would it be a deal breaker for me? Not sure, as I look at the whole package, its its just one factor in the mix. If it was your typical tiny sun/moon roof, then I doubt I would bother but the big one on the Forester is real nice.