The Endorphin Elite 2 is the shoe Saucony builds when nothing else matters but the finish. IncrediRUN foam sits under a full-length slotted carbon plate, the drop is 8 mm, and the whole thing weighs about 199 g. It returns energy in a way a normal trainer cannot, and it does so at every pace including the ones you did not ask for.
It suits you on race day, from a fast 10K up to a marathon, and it suits you best if you are already running quickly enough to load the plate.
It is not a trainer and it is not durable. The upper is barely there, the ride is unforgiving at easy pace, and the foam is spent long before an ordinary shoe would be. Buy it to race in, and race in it sparingly.