I have one and I love it! It is a specialty lens that needs to be used carefully. It's not the fastest lens out there, but when used right it's a spectacular lens. My copy has never shown me anything but being a sharp, UWA lens.
Examples:
10mm 1sec. @ f6.3 ISO 100
18mm 1/4 sec @ f4 ISO 100
18mm 1/8 sec @ f5.6 ISO 100
13mm 1/10 @ f4 ISO 100
10mm .4 sec @ f4 ISO 100
11mm 1/200 f11 ISO 100
16mm 1/250 @ f5 ISO 800
12mm 1sec. @ f6.3 ISO 100
Is that enough Tamron wide angle maddness?
Color rendition is very nice and correct as well as it's contrast. Over all I am very happy with my Tamron 10-24 SP f3.5-4.5.
For more wide angle shots with this lens, please look at this flickr page.
http://www.flickr.com …g/sets/72157623305410656/