Tamron makes great glass. It, like other lens manufacturers sometimes assemble duds. It seems to be a fact of life. Even Canon seems to miss from time to time.


The last Tamron lens I purchased new, I took a print of a focus chart to a local store that had 2 copies and tested both copies. The first was terrible but the second was perfect. The owner and I were both suprised at the results.


Ask the owner to let you take some shots with the lens mounted to your camera. Take your tripod in/or use timer to test the IQ on a target scene or focus chart. You will be happy you did. Do not evaluate with handheld slow shutter/high ISO shots. Always evaluate a lens non handheld/low ISO.