Well, just some comments, I still have my One and pulled the sim out about 3-4 weeks ago after I got my N5. I figured I would try it and then the loser goes to my son (I pay the bills I get the goods!).
So, I've not put the sim back in the One since I got the N5. The One sounds better, especially with the viper4android app, has the ir blaster and looks pretty good. I also was running the SinLess GE rom and loved it.
But...there is something about getting the ota's within hours on XDA for the N5. It took about 5 minutes to root and drop in a custom recovery. I feel no need to flash a rom, Kit Kat is excellent. Getting back to the phone, the screen is immersive, its insanely fast, 0 lag. I don't know what ll the hubbub with the camera is, works excellent, really have no issues, its not a DSLR. It feels good holding it, seriously, the tactile feel of the back feels good.
My intent is not to convince you any way, but as someone who is passing his One to his son, (I have this dang mobile pass app from work and can't get it copied over to my phone, so I still need it) the N5 is just about everything I want in a phone. I gave up my iPhone 5 for the One and the One for the N5 and have no regrets. Good luck with whatever way you go, you really can't lose!
Nexus 5 - ATT; Rooted, Custom Recovery, Stock ROM
HTC One - ATT; Rooted, s-off
ROM: SinLess ROM GE