My experience is much more limited than Phil's tho for longer, I'd guess. Ignorance spread out smoothly over more time, maybe. Like peanut butter.
Anyway, my experience with certain brands is that the factory tune is sometimes good. You gotta try them to tell. (And I wouldn't bother trying with some brands.)
With Atomics, factory has been so far good. For instance, I've gotten three Atomics in the past two years, and all three were well-tuned from the factory. In fact, for some reason they usually feel really spot on in a way I haven't been able to quite duplicate tuning myself. (Though in some ways my tune is better: sharper, more consistent edge, for example).
Kastles and Stocklis I've had similar great experiences with.
Rossis are another brand I've had good luck with, though not as much. I tried out a friend's E-88 that still had its factory tune that sucked. But my Exp. 98s were factory well-tuned, even though they were 1/1. And they were a lot of fun at 1/1. (with the minor increase of tip base bevel, mentioned above.)
Still, they definitely improved across the board after I hand-tuned them, with a 1/2 at first.
With this particular ski, and its partner, the E-88, I can see where Phil is coming from in one way: there is a smoothness to the edgehold with the 1/2 that in some ways really suits these two skis that already have such pronounced carve/grip. Generally I strongly prefer the 1/2 over the 1/1; and often prefer the 1/3 over the 1/2, though there's a slight trade-off. But in this Rossi case, I liked the 1/2 (compared to the 1/3) just as well, different but as well: smooth vs. grippy on an already grippy ski.