I am a user of Western digital USB disks from the last 6 years. I have purchased 4 disks in last 6 years at different times and have not faced any problems till now. I trust WD. Coming to the "Elements vs Passport", the major difference being is that the Passport version is that it is more latest, has some software on it [which you might not use] and latest firmware, Look wise both are of same quality, dimensions.
I have 1 TB passport version and 2 TB elements version now. So, after doing lot of research, I settled for Elements and to the product on Amazon site, because, it offered the best price in the market. Overall very satisfied with the product and quality.