I have been in the flooring business for over 15 years and i believe as far as durability is concerned pre-finished engineer flooring I much more durable, and now your color choices are nearly endless. Lets also remember solid hard woods finish is only as good as the re-finisher and the products he uses. so there is a much lager room for error.
Solid Wood: The Basics
Solid wood is just what its name implies: Each plank is a solid slab of wood, usually about 3/4-inch thick. A traditional floor often has 2 ½-inch-wide planks, but for a different, usually more rustic, look, you can opt for planks as wide as 6 inches. A hardwood floor can be finished in your kitchen for a truly custom look, though that means additional down time for sanding, staining, and sealing. Pre-finished planks let you use the room right away; however, you have to choose from the colors the manufacturer offers.
Is it really a "greener" choice if you have to replace it after 15 years? We have a house from 1945 with hardwood golden oak throughout. The floors have been refinished once. At that rate, the floors should last for 200 years. Pretty green to me...why pay almost as much for 1/3 of the product?
This would have been much more helpful if the species of wood and types of finishes used would have been posted with the photos.