Originally Posted by vagarach
Only professionals who need to be sure their lenses can take a few knocks and are sealed against dust and dirt should be 'steering away' from the 'lesser' lenses in Nikon's and Canon's ranges.
Even if the idea is to use the gear regularly, you don't have to drop thousands of dollars on pro glass when you're not actually making the same demands on your gear as a pro! The all-metal bodies might be strong but they also weigh a lot more, and easy-to-handle cameras are more fun to use.
Most amateurs treat their cameras a whole lot worse than most professionals. The cheap lenses generally will have optics that are not quite as sharp and don't perform as well across the field of view and or at aperture extremes, and are 1-3 stops slower...and more importantly they often do not auto-focus nearly as rapidly if that is important to you (if your subjects are frequently of the moving variety). Plastic lenses and bodies are far more likely to break down sooner, and the attention to construction paid to pro cameras and lenses is apparent when you handle the two side by side. If money is an issue, then I guess this all should be weighed out appropriate to your own personal needs. You definitely get what you pay for.