It depends on the situation. This is first zoom lens I actually use a lot. (I'm a pro with 30+ years doing travel editorial and commercial work). The 16-55 has fine image quality across the range. But besides that it allows me to be safer when I'm shooting a changing situation, like walking backwards, (or forward), in a field or on the street. Or, getting the shot because I could zoom faster than I could change lenses. Two bodies with primes? Yes, sometimes, but that can be physically awkward and also distracting for some subjects. So this upcoming trip to Vietnam where I'll be shooting a rice harvest will be primariy the 16-55 and 55-200. Additional 2 bodies with primes: 18, 27, and 35 f2, for back-up and night shooting. Leaving the heavy primes at home. Taking a carbon fiber Gitzo.
