50mm f/2.8 EX DG MACRO LENS (CANON AF)

great close up shots - best if you use manual focus

none really but getting so close to stuff means you need a plain or UV filter to protect the lens

Excellent sharpness and quality of photos. Auto-Focus is pretty good too (did hear off a few people before I bought it could be awkward).

The only bad point I could find is it tends to be a little noisy when focusing, but I wouldn't say it's a major problem.