I'm sorry, but how is the HTC One any better than the Butterfly?

I've been searching long and hard for my next mobile phone, and it just so happens that I pulled over by HTC's side of the market.

Admittedly, I have been intrigued by the One, and look upon it as potentially my next phone. However, just browsing through HTC's catalogue, I've noticed the HTC Butterfly, and have been sitting in my chair for the last hour or so trying to figure out exactly what the One does better.

Both phones have quality, 1080p displays with very high pixel densities. They're both equipped with Beats Audio, Snapdragon processors and Adreno 320 gpus.

BUT, and there is a big one, the Butterfly has a noticeably better camera(please don't bring ultrapixels into the mix here), and expandable storage. On top of that, I find the design more comfortable and ergonomic.

It would be nice if anyone could point out the obvious differences, as I honestly don't see any.