The last first-party case that I owned from Apple was the black leather iPhone SE cover. Which lasted me, solidly, around 9 to 10 months before it started to tear itself apart. I really liked the leather feeling on my hand. It added a nice grip to it. The problem with it is that leather is not technically water proof, and the smallest accident of leaving your phone in a wet surface will make the leather to swell and smell.
I upgraded from the iPhone SE this week to the massive iPhone 7 Plus. I didn't decide right away which case to get, but the previous day before getting the new phone I got the camellia sport band for my Apple Watch, which looks and feel wholly nice.
Taking that in consideration, I went for the camellia silicone case for the phone.
I will give a final number rating after a month to see if it get stained or if it holds itself gloriously.