Devil's advocate here...
"Cobra’s line of King F7 irons use a progressive club head design, which the company calls “TECFLO,” to meet the specific performance needs of each irons. That means the long irons (3, 4, 5) have a full-hollow design, the mid irons (6 and 7) have a half-hollow construction and the short irons (8-PW) have a cavity-back design. The 3-7 irons are cast from 17-4 stainless steel and use a milled 17-4 stainless steel face insert, while the short irons are cast from 431 stainless steel. Each of the irons also uses what Cobra calls “PWRSHELL” technology, which means that the faces are made thinner and sole structures are designed to increase the size of the sweet spot, thus producing higher ball speeds more often."
So they kind of do, but not touting it for the same reasons that others have. Their explanation actually says what I have said all along, the idea of a "hot" face iron, really is about getting over the water on a mis-struck shot, not about the theoretical extra 5 yards on a perfect shot.