LOL, there's probably at least one in every single location
The reason it's so common is probably that it's made of the most common material: Iron. And Beth couldn't be bothered to make more than one design per material type, which is just poor in my opinion. They could at least have made all the designs available in all the materials, i.e. you could make the Steel Plate Armor in Ebony if you so wished, but apparently that was too much work.
Anyway, I've worn it, but I prefer the Helm of Yngol or the Ancient Nord Helm. I think they're all cool. Right now I'm wearing all Steel Plate with the Horned Steel Helmet, which looks awesome. Best looking armor in the game.