I just bought a 5D3 - upgrading from a 7D. I need a good walk around lens to put on it. I take lots of low light pictures. Image stabilization is nice, but not that important to me. The extra stop in very important. Money is also a big factor in the purchase. I can't bring myself to pay the ridiculous price for the Canon 24-70 II. Whatever you may say about the quality - it's just too expensive. That brings me down to a choice of two lenses - the Tamron 24-70 f/2.8 or Canon 24-105 f/4.
Yes - I have tried out both lenses, shooting a few shots in a store, but never handling one on a long term basis. The 24-105 is a great lens, but I hesitate because I would really use the wider aperture in a 2.8 lens. The Tamron - I've tried two copies. One was awesome, one was terrible. The AF was fast in one, almost broken in the other. It was slow and shook right before it locked on. The picture was sharp in one and soft in the other. This scared me, but if the one was just a bad copy, and I ended up with a good copy, well maybe it would be better than the Canon lens.
This question was asked on this forum a couple times already and most responses were comments such as "Canon lenses are better because they have 'Canon' written on them," or "get this other lens that you didn't ask about."
Seriously... between these two lenses - from people who have shot with both of them, what would you recommend, considering the build quality, sharpness, resale value, long term reliability, etc. ? And of course there's the aperture thing.
Thanks in advance...