If the pants are anything like the quality of the Butt Naked undershirts, they will be good.
Since I wear a tall shirt and there are few dry fit tall shirt options, I bought a couple of the Butt Naked undershirts as workout shirts.
I now have 1/2 dozen. I've had them for a few years now. They are much more durable than regular cotton undershirts, and since tall sizes in those were more pricey, other than the initial price, it's more cost effective to buy the DT undershirts.
Can't say anything less than good things about the DT products I've used.