Yes, knee pads with upper shin coverage are a great choice for all-mountain and mogul skiing. They extend protection below the kneecap to cover the upper shin, which is a common impact zone when you're skiing bumps, crud, or variable snow. Your shins take a beating from boot contact, ski edges, and hard snow spray, so that extra coverage really adds up over a full day.
The trade-off is a bit more bulk compared to kneecap-only pads, but modern designs keep the added profile minimal. Most skiers find that the slight increase in size is well worth the protection for anything beyond groomed runs.
If you primarily stick to smooth groomers or casual resort laps, kneecap-only pads may be all you need. But if you're charging moguls, skiing tight trees, or exploring the whole mountain, the knee-plus-shin combo gives you solid protection right where you'll appreciate it most.