Help with Lens Choice

[littleduno]

I'm in the process of choosing between two lenses for my Canon EOS-1V. The 24-70L is in my sights for a future purchase but due to its price I need something in the meantime. I'm down to the Canon 28-135 IS and the Tamron 28-75 2.8. This lens is something that will be on the camera most of the time for family shots, vacations, etc. I already have the 70-200 f4 for sports and nicer shots. Does anyone have any opinions of these two lenses? I've read the reviews and the Canon 28-135 really seems split, though overall it rates well. If anyone has any input, I'd really appreciate it - thanks!

[another view]

Here's a review on the Tamron: http://www.shootsmarter.com/infocenter/wc006j.html
Personally, I'd go with a constant f2.8 lens over a slower variable aperture lens with IS any day.