When i was looking at the S4 and the htc one there was a lot i liked about the S4 when making comparisons to my daughters s3
1 The amoled screen has never been my favorite but the S4 really looks better than the S3 From a true blue lcd guy i do like the improvements Samsung made in this iteration of the S line
2 Screen size when compared to overall size has also been improved. For a near identical sized phone you get more screen to look at.
3 Sheer processing power. I didn't notice a huge difference over the S3 but the S3 was a very snappy phone in its own right.
I did notice a bit of stutter but nothing crazy like the huge lag stories i've read. The S4 (in my opinion) would be a nice upgrade if you're coming from the S3 but not at full price.
At the end of the day i did go with the HTC One but the Samsung S4 was a strong second
Sure Htc One and S4 owners bag on each other a bit in the forums. Partly for the fun in it lol and partly because we just really enjoy our devices. The S4 has a lot of reasons for people to want to buy it as does the One.... True story