Primes have a few disadvantages: covering a range in primes is heavier than the equivalent zoom. If you’re a Galen Rowell wanna-be (me, too — long ago) and clambering up mountains, pick a single prime for the trip. He used a 20mm f/4 for getting a camera places most of us thought just weren’t possible.

If you have multiple primes along, you need to be at least moderately good at switching lenses. Practice over something soft, like a bed. Primes are more sturdy than zooms but neither will stand up to bouncing on a hard floor. Learn to do it with the camera opening pointing down. Even so, you’ll find yourself cleaning sensors more often (easy once you learn how). If there’s something abrasive blowing around (windy day at the beach), shoot with the lens that’s mounted — or pass up the shot.