Product review (4 stars): Very good
This review pertains to products sold by "Supply Edge"

These are nicely made (in China).  They are formed perfectly flat, which ought to help minimize the hotspots that lead to premature failure.  I bought two of the 6" and two of the 8".  In the 30 year old range top, the 6" burners popped in perfectly.  Not so with the 8" -- see that review.

They are shipped in sealed poly bags without any protection for the electrical contacts.  Of the four I ordered, three contacts required straightening.  They're fairly soft, so it's not difficult to bend them back into alignment.  This problem could have been easily avoided by surrounding them with a simple cardboard sleeve, which they ought to do since it looks like typical handling can and does cause some damage. One star off for inadequate packaging.