How long would a tin of American Crew Fiber last if you used it for 5 days a week.

I have 2 inch long hair, and was wondering if it's worth the price.

Product in Question:

http://www.amazon.com/American-Pliable-Molding-Styling-Creams/dp/B0008IV7BU/ref=cm_cr_pr_product_top

Also, what's the difference between the the two 3oz tins? There's a price difference, but nothing else?

Thanks!