I am installing interior window and door casings in my 1940s bungalow. The casings are 4 1/2" wide post and lintel style...no miters. I am going to have to get 1"x6" boards and rip them down to 4 1/2". All casings will be primed/painted. My question is whether there is any difference between yellow pine and spruce (whitewood) in this application. The whitewood is a good bit cheaper at the lumber yards here, but I have never used it before. Any advice?