I'm new to DSLR and just starting to buy equipment. As my budget is pretty small, making good purchases is pretty important to me. Before I invest in equipment I read a ton of reviews... so much so I can get a bit overwhelmed at times. After reading some reviews or various lenses I see that some people get "good" copies and some don't. It looks like most retailers/manufacturers are pretty good about exchanging the "bad" ones.
When you first get your lens is there a series of tests or checklist that you do to determine if your lens is good?