"What does it take for a lens to be worthy of a T5? That's not exactly a high-end camera."
Yes sir, you are correct! The T5 is not Canon's top of the line. But Promaster is at the bottom of lenses. The T5 is can take outstanding photos but not when equipped with junk. Don't waste your money just because the budget may be tight. That usually winds up costing you more in the end!