Pros: Cost, weight, focal range, sharp enough for museum quality.
Cons: I don't have too many complaints about this lens.
I bought the Quantaray 18 to 50 mm lens specifically because I needed the wide angle to shoot the interior of a historic church for a commission assignment. As a wedding photographer, all my lenses were designed for film cameras and I really did not need (or have) the super wide angles after I switched to digital.
Then, the Pastor of the Church where I did the most weddings called me and said that the Curator of a museum was looking for a photo of the interior and he thought of me.
Well, I did not want to put much money into a lens for a one shot assignment, so I found this lens at Ritz.
I put it on a Nikon D-100, put the camera on a tripod and stopped the lens all the way down. I shot away on the RAW setting' bracketing both in color balance and exposure.
With some color tinkering on Photoshop, I delivered the images to the Curator and they enlarged them to 4' X 3'. The images are beautiful and the museum is very happy with them. The image is permanently displayed at the museum.
This has become my favorite lens. It is small, easy to carry around, especially on the lighter D-70 body and it's range is perfect. I don't do weddings anymore, but I did use this lens on the last few I did. I put a UV filter on it and found a wide angle metal lens shade (B&W - which probably cost as much as the lens). If you don't think the front of your lens takes a beating, put a metal lens shade on it and look at it after about 2 months.