Tamron SP AF 28-75 f/2.8 Macro Zoom Lens

I've always favored single focal length lenses because of their superior optical performance. Back when zoom lenses were first introduced, they usually didn't match the performance of a prime. Zoom have gotten better in the past 40 years, but getting a fast one meant getting a heavy one. When I recently pored over reviews of the Tamron SP AF 28-75 f/2.8 Macro Zoom, I was surprised that it was so light compared to my Tokina zoom of the same focal lengths and aperture. The price was right, so I ordered one.
Unlike many zooms from the recent dSLR years, the Tamron covers a full frame rather than an APS size frame. Its weight balances nicely with a full frame dSLR (whereas my earlier Tokina is very front-heavy).
I have had a chance to shoot about four hundred frames with it at a recent pet fair at my college. The sun was blazing bright on the first day of fall, so I shot mostly in the shadows. My impressions so far are good.
The picture above is not technically perfect since the pooch was in a state of perpetual motion and, at 1/200 second, is a bit blurred. The aperture is f/3.5 shot at an ISO of 200. My reasons for choosing this frame is to show the sharpness at f/3.5, and the pleasing (IMO) bokeh when the lens is nearly wide open. Click on the image to see it enlarged.
The photo below is at the far end of the zoom range (75mm) and at f/4.0 at ISO 200, 1/160.

No sharpening in PS, direct from RAW with some color adjustments to remove the bluish tint from being in the shade. A crop from the dog's eye looks pretty good to me considering I wasn't using a tripod.

Virtually everything I shoot is with focal lengths from 28 to 75, so this lens can be the only one I tote around. I look forward to putting it through its paces in the coming weeks.