I have to admit. The Vikings current helmet is pretty awesome. The dazzling purple background is a showstopper, and the viking horns are a no brainer. My only issue with it is that the viking horns are just a tad too big. Some of the redesigns really fix this issue, like the top right and bottom right especially. Their horns are just a tad bit smaller which really helps for clarity. The top right has a top half that is gold, evoking a vikings hair, which is an especially nice touch.
I'm also a big fan of the bottom left which is a little more of a modern approach to the design, using stencil-like images instead of cartoon depictions of the horn. That being said, why go subtle when you are dealing with a viking?