Basically the base is not flat, not flat in the right place, is a combo of concave and convex, who knows; the base bevels are inconsistent, or the edges are higher than the base. Sometimes all of the above. Structure itself is sort of a non issue.
You need a true bar and a back light source.
Maybe
@Primoz has suggestions for checking new skis. I suspect his skis generally come with worldcup level tunes though, not from a consumer store.
In general, skis are better finished than several years ago, but they're's still big problems. Ten years ago most Heads were atrocious.
The one V82 I had you had to throw it on edge. Then throw it to the next edge. And I mean throw. A real pain for six hours, but not a bad excercise. I've had worse, much worse, but hard snow would have made it really bad.
Note that Ron skis Steamboat's Champagne Powder
tm which even when compressed turns into a decent sparkling wine.
If you have a good tuning shop that you trust, take the new skis there before mounting imo.