I put one of these in for a customer about four years ago. A 4 panel with a 1/2 moon window. It was stained it with a solid pigment stain. Faces West and gets brutal Sun. Has held up great. Even with a black storm door the plastic holding in the window has not deformed a bit. The unit ran about $775.00 as I remember. I have no problem recommending this compamy.
Therma tru puts out a quality door. Just recently did a replacement with my front entry door with two side-lites. The door has 3/4" oak jambs which I stained with conventional wood stain. If you go with Therma tru, get their stain kit which includes the fiberglass stain and a satin clear coat finish. Therma tur has a web site which will help you with installation and staining. When you get to the staining of the door remember to put the stain on with a rag and then using their brush and another clean rag "work" the stain with the brush and dab the brush into the rag to lighten up the stain. After I finally completed the door the fiberglass looks better the and oak trim.