Product review (4 stars): It lasted 1 year and 1 week
Was the part I received genuine Whirlpool?  There was no identifiable branding on the box, instructions, or part.  I can confirm that it was not a Napco, which I was replacing and do not recommend.  So, I'm prepared to give the benefit of the doubt.  The coils are diagonal, just like in the picture.  A single sheet of instructions is included.  Be sure you first unplug the dryer!  I was done in half an hour.  The hardest part was getting the exhaust vent reconnected when the job was done.

***  Update :  Purchased March 3, 2015; failed March 10, 2016.  My dryer is subjected to a lot of vibration from a nearby front-loader washer, which may be causing heating elements to fail much more quickly.