Well, what are you planning on putting on the phone? Are you going to use it as a camera/music player and everything else like a small tablet?

Personally I have the 64 GB and 35GB is already full because I have all of the music from my computer on it and I have never deleted a pictures/videos that I have taken from the phone (about 400 pictures/100 videos).

If you are just going to use it as a phone and maybe some music then save some money and get the 16 GB but if you are going to use it for everything you do then get 64 GB. 64 GB is a lot of memory and not many users need it. Hope this helps you a little! And when I got my phone, I was so ecstatic, I didn't even go to my classes and waited till the phone and opened it up right away lol