It won't affect most people, but I see a well-known cloud drive being reduced from 15Gb to 5Gb. They apologised. I'll try to find the link.
I don't use clouds at all.
The contact transfer between my Core Prime and the S6 was seamless. The issue was simply making the contact appear on the home screen. Without the use of widgets. It seems that prior to Marshmallow it was a two-touch process. (assuming you're already looking at the contact.)