I've had the same RCBS inertia puller for about 30 years now. The inertial pullers are so easy to use and, with a bit of paper towel stuffed in the bottom, never mark the bullet. The trick is, especially with factory or crimped ammo, is to seat the bullet just a bit deeper to loosen it before trying to pull it. Also, the term "inertia hammer" should never be used! It's not a hammer! I broke a few of those things before I figured it out, now I've used the same one for years. Tapping the hammer on something solid, like concrete, works best, using only the wrist (never on wood or carpet!). You can whack it hard but you're wasting energy. Just use the wrist, hit it on something solid after the bullet has been broken loose, and keep the cap tight so you don't beat the stuffing out of the collet and you'll find the bullets come out easily & quickly. Of course, the lighter the bullet, such as .22's, can require more hits, while heavy bullets will pop right out with just a few taps. Once the technique has been mastered, the pullers last nearly forever and work amazingly well.
Cheers,
crkckr