Which Tamron Lens should I purchase for a Canon T3i (video production)?

Which Tamron lens should I buy for my T3i for video production>

I need something that's good all around: interviews, outside/inside b-roll, crowd shots.
Most of the videos I do are interview, corporate, and educational.

My next project is going to be at a festival that will have a lot of dancing and festivities. A lot of it will be at night. I am also interviewing a lot of people. Please recommend me a good one.

http://www.amazon.com/Tamron-28-75mm-Aspherical-Canon-Digital/dp/B0000A1G05...

http://www.bhphotovideo.com/c/product/851798-REF/Tamron_AFB005C700B_RBT1750...