GAF (and this thread) is a prime example of how we rarely know best, because we rarely agree!
SD card vs internal only
Plastics vs Metal/Glass
On screen buttons vs capacitive
Stock vs Touchwiz
So much of this stuff is subjective, even something like camera quality. I'm not sure if there's anyone in this thread with enough proper testing of both phones camera to compare, but I could be wrong. I'd suggest visiting Anandtech who normally have very, very detailed reviews. Both the HTC One and X have had camera improving software updates.
If you want me to suggest a phone overall, go with the X. I don't think there's going to be too much in it camera wise, but the customization, pretty much guaranteed swift updates, battery life, near stock android with useful tweaks and price would swing it for me. Moto maker if you can. I think the build of the One is nice, but sense is nowhere near as user friendly as stock.
That's a very subjective opinion though, others may disagree.
Oh yeah and get one with a wooden back. That shit is drool worthy.