[lgieron]

In my experience, the more expensive brands are no more reliable. Cotton t-shirt is a cotton t-shirt, there isn't much you can make to make it more durable. You could use a thicker fabric, but then it would not be the same t-shirt. The only option available that comes to my mind is using more resilient dyes.

[dagw]

using a higher thread count and better stitching has a significant effect on the durability of a t-shirt. But those aspects are only weakly correlated to price.