For me this ally has immediately become one of the new defensive staples, right alongside the Defender of Rammas. 3 Defense is really respectable, and 2 hit points let it avoid some of the more annoying treacheries or shadow effects. The Response is pure gold, especially in a trap deck or in a staging area attack deck (Éomer or Dúnhere will thank this little guy a lot) as a sort of Fastred alternative. I will almost always include these guys in any deck which includes Lore or has a pure Rohan hero lineup to take advantage of the Devoted keyword.
10/10 would defend Helm's Deep again.