Samsung Galaxy S4

Pros: Removable or Changeable battery
Good Hardware

Cons: Requires Root to get rid of bloatware

Summary: I have read a lot about HTC one and Galaxy S4 comparison and they are only natural as these represent 2 best smartphones of 2013.
Yes, I take that HTC One has great looks, beats audio and fresh design... but what you need to give away for that is ability to change or upgrade the battery.
Any battery however good is it charges for 500 cycles if all the connections remain proper.. For a smartphone, its easy to achieve these cycles in 18 months or so..
Do I want to replace a 700 USD phone in such a short time.. sorry, I don't.
Moreover, if you look at some suppliers they give fatter batteries with replaceable covers. SO if you are on the move then it makes sense to change the 2600 mAH battery with 5000 mAH and still retaining reasonable looks, thanks to super slim structure of S4.

Come to the other difference, HTC One has LCD screen and it is common to have dead pixels in LCD after some time. AMOLED screens have no recorded problems like this.

Yes, the audio requires improvement but the included ear-phones house woofer and speaker to get a much rounded sound. Who listens to music or takes calls with speakerphone generally?

Now the plastic, well its much more likely that your phone will survive a drop if its plastic rather than polished metal design.

At the end it will come to personal preference, I have some bad exp. with HTC and their is a huge developer community doing things for Samsung, I fear being left out of exciting customizations like I did with my Dell Streak..

GS4 is for me..