I shot factory Federal Premium ammo for years before I started reloading. Every single one of these factory ammo primers were always flattened after being fired in my M700 7mm mag. Fired primer inspection is something that I always do with my loads, but I think it is more of a relative parameter as long as you aren't getting some type of more dramatic deformation. The primers in my spent cases of my hand loads look identical to the spent primers from the factory ammo I shot in the past; flattened. I use federal primers and always have, so I am not sure how other brands of primers would look. You also need to pay close attention to any changes in how the bolt handle lifts after firing (hard to lift) as well as inspect your fired brass closely.
Hope this helps
Hope this helps