I just bought a used Oly 50-200 SWD from a reputable online vendor. While the glass looks good and the lens seems to be mechanically fine, I'm concerned about pretty serious finish wear. Looks like it spent a lot of years being bounced around. I'm still within the vendor's return window. But before deciding whether to 1) ask for a price reduction or 2) returning it I'd appreciate hearing opinions from others who own this lens. Is it designed to take rough treatment or should I assume that the finish wear = unacceptably careless use? Thank you in advance.