XZ is waterproof. S4 and One are not.
If S4 Active comes out, it will be as pricey as S4 launched.
S4 price is steep. And it looks the same like S3.
Should be water resistance.

not deal decider for me actually, I had drop many electronic hardware into the water and use them under the rain, none of them had shorted yet. good to have but not essential.
me had the same dilemma.
s4 htc1 or sony z.
chose sony z cos its the cheapest lte phone ^^
1080p 13mp (altho cam sux)
of cos sony z looks better than the rest
sadly the 13MP isn't better than 8MP of last year, still, good enough for a phone camera.
if you are looking for benchmarking, XZ will lose out but by not a lot if you take the slower spec processor into consideration. Other than that design is personal preference. Also samsung has touchwiz which I personally rather not have. Also XZ is water/dust resistant.
But if you already have HTC one, why buy another phone released in the same period, I would say wait for the next version of Xperia Z.
I don't care much about synthetic benchmark, coming from HTC Sensation, any current flagship is lightning fast to me.
I had Omnia II winmo phone for 2 years, and I will never want to go near any device running the similar UI anymore. even after 4 years, touchwiz still looks very much alike, at least the color scheme, icon and fonts. one of the reason i don't like the galaxy line.
Phone is for my father, he was also using Sensation, the first version. I recon the bigger screen would help for older person. also, Sense 5 UI had change quite a bit and theres only 2 buttons layout. would probably like a new UI to him, so One or XZ are both alien UI. actually, if Butterfly is still around, I would have get it for him. unfortunately, the $100 Starhub voucher will expire before the new Butterfly S reach our shore.
Just watch the Chinese review of XZ, very objective. I more or less know the pros and cons of XZ now.
p.s. I didn't know XZ use TN!
