Originally posted by gaweidert 
I am in the same boat you are. I am going to buy the Sigma 150-500 but cannot nail down a leans in the 70-210 range. Every time I pick one I change my mind. I am torn between the Sigma 70-200, The Pentax 60-250 and the Tamron 70-200. I can list a half dozen reasons why each would work for me Currently I am using a Tamron SP 70-210 F3.5 for the role but it is starting to show it's age. I only went digital about 2 years ago and only have one auto focus lens. The Tamron I am now using is pretty handy. One control for zoom and focus. A very good reputation for sharpness and it goes macro too.
I think the Tamron will probably fill the bill for me best. The Sigma had the OS and fast focus, but I have read the same thing about being a bit soft. Plus it is $400 more expensive.
The Pentax 60-250 seems like a great lens, but I still use film once in awhile and it would not work on a full frame camera.
It appears that there is alot of people having difficulties in Pentax 70-200 range. So far Tamron 70-200 f2.8 seems like the best option considering weight/autofocus speed/optical quality. It will probably feel bit toyish as my current tamron 17-50 f2.8 but i am sure it will last long enough.
As for 60-250 i read somewhere that there is some vignetting at FF but not sure if that will be a huge problem. I am pretty sure that some lenses like DA*200 covers FF.
Unfortunately i am, still, bit young to remember glorious days of film. I had a Nikon F3 and current have a Pentax ME Super but i can agree on both the quality of your tamron + its age. I love manual focusing( but cant focus well at f1.4) and i do have alot of M42 lenses along with my autofocus primes but still 1-2 zoom lens is always handy to have.
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