Of all the bands from the 80s still making Thrash albums Overkill is at the top of the heap, with maybe Kreator just above them. Ironbound and The Electric Age are very good albums. I hold Ironbound and The Electric Age in the same high regard that I have for The Years of Decay and Under the Influence, and slightly below Feel the Fire and Taking Over.
I need to give the new one more listens, but it surpasses anything Metallica, Megadeth or Slayer has done recently. I don't include Anthrax because I consider Worship Music the best thrash album from the Big 4 since Megadeth's R.I.P.