Sony Xperia Z or Samsung Galaxy S4 comparison, which is better buy ?

Since today my friend is facing problem with sony phone he purchased yesterday, I have changed my mind. I am sony lover from long but phone of my friend is giving problem so I decided to know which is best phone now from Samsung Galaxy S4 and Sony Xperia Z. I know Samsung Galaxy s4 has some new features but I also loved sony xperia, speically its look is awsesome while S4 looks plastic type in front of Xperia S .

Both phones are high phone, anyone having any experience , from my side I find Xperia very good and attractive but since faced problem of not booting up , I am now not very interested towards this so called high end phone.