I've never owned the HTC One, although I've fondled them at the stores. They seem very well made and I really like the dual, front-facing speakers. I'm all about the battery though, so the Maxx HD is (was) the phone for me. I really can never go back to a phone with a battery smaller than 3,000 mAh.
That said, I'm getting ready to jump ship to the Samsung Galaxy Note 2 or 3. I really like the larger screen and many of the offerings of these phones plus they have a great battery. Another plus is that you can change out the battery. My Maxx is a year old and already I'm noticing that the battery is not holding as great a charge as it used to. And since you can't swap out the battery on the Maxx it will only get worse.
I really enjoyed my time with the Maxx and they set the battery bar quite high but now that it's been match it's time for Motorola to play catch up.