Help me in selecting.....
I do not own the other lenses you mentioned but have and use the Tamron 70-300 vc. So, I will give you my hopefully educated guesses about your situation. First and foremost, the Tamron has an excellent stabilization system--the vc. I don't believe the other two lenses have stabilization. I can shoot the Tamron at 1/60 on my D90 and get a high percentage of keepers hand held. With the other lenses, you will most likely need support. While the Tamron is relatively slow at 300mm and f 5.6, I enjoy shooting it wide open quite often. So, in a way, you gain speed. It is likely you will need to stop the older lenses down to gain sharpness.
So, if you see things the way I do, you will find the Tamron to be an excellent choice. But, you might want to see for myself. I bought mine from a brick and mortar store that gave me the option to return it after five days of unlimited shooting. The second day was not needed. The lens had me at hello.
While I use the lens for a variety of purposes (sports, flowers, portraits, etc.) you can see a number of my shots with the lens in my gallery here or in the flickr stream linked below--many are in the soccer and skating sets but others can be found throughout.