[...] O.K. to tack with the finish nailer. They are pretty strong as long as there is not to much pressure or weight on the members.
agreed on the amount of weight they can handle, but my PC finish nailer, I dont know about yours, only holds nails between .75" and 1.5". If you need to go through anything bigger than a 2x4, the nails aren't reliably set enough to hold something square, at least in my level of relative inexperience.
-skinny