Ok, this may seem like a strange question but I'm getting ready to hike the Camino Norte in mid-June. I have convertible pants and a good pair of hiking shoes (Alta trail shoes). Any suggestions on shirts and underwear. It seems a lot of people swear by anything made with merino wool but its terrible expensive. I've seen merino wool underwear for $60. I can't imagine everyone walking is wearing something so expensive. Are there good alternatives? I did get a couple of Columbia shirts made with polyester. Is this a good choice?