For target i buy whatever is cheapest.
That is were it will get expensive, making sure it works flawlessly with your gun. Other then that I personally think it would be worth it to have a couple mags loaded up with them just in case. In my perspective, its still cheaper then my .50ae rounds I buy....... I just like to fire a couple hundred rounds of something thru my gun to make sure there are no problems with feeding before I rely on it in a defensive situation.......