I have had my one S for nearly two weeks now and have to say it is a fantastic phone, I have been quite fortunate that I have not experienced any of the issues read about online so far. I did buy a casemate tough case almost immediately though as the phone is very thin and slippery and I could see how easily it would get damaged or scratched, some change in my pocket left a mark on the back which luckily wiped off!
I did try the One x but thought I would probably find it to big for day to day use. The one S is a great improvement on my Sony xperia!