I would stay away from Palm Harbor. After touring their Austin, TX plant, I learned that they do not use a regular roofing felt or paper under their shingles, and they do NOT use a vapor barrier between the exterior siding and the frame of the house. This can be very important in Dallas. You need a good vapor barrier to prevent the buildup of mold or mildew in the walls, and you need regular roofing felt (15 lb. or 30 lb.) in order to stand up to the storms in the DFW area. Instead of regular roofing paper, they use a brown paper with a VERY thin layer of tar between the layers of the paper.
I don't know what other brands include these features, other than House Smart. Check with Randy Eaton about other brands.