If you have a choice between engineered and solid wood, go with solid wood. But if you're installing on concrete you really don't. The aluminum oxide finish on engineered wood is much harder than any finish you can apply after a floor is installed, so engineered wood is pretty darn durable. But you really can't sand it much (depends on the wear layer), so your options for refinishing are limited. You're unlikely to wear through the wood layer by walking on it or dropping something, though.