How is your case holding up? I love the way the new silicone case feels when you first take it ouf of the packaging but then it gets more rubbery after a few days of use. Would love to figure out how to get that "just out of the packaging" feel back.I had both leather and silicone for my 6 Plus, and have both for my 7 Plus.
I change them out from time to time. As for cleaning, etc I just use rubbing alcohol on the silicone cases; that removes any grime or dirt or whatnot. As someone said earlier, the silicone case will feel greasy after a while---mine does that as well, but 20 seconds with a cloth and some rubbing alcohol will restore the case to a new feeling.
As for leather, I clean mine with leather cleaner; some dye will remove, but not enough to make the case appear discolored.
I've also used rubbing alcohol in a pinch to clean the leather case, and made the leather feel tacky.
I've never had the issues of peeling with either case, or corners tearing, etc.
Also, my 6 Plus has no scratches, scuffing, etc on the backs or other areas covered by the Apple cases.
As far as protection goes, I never damaged my 6 Plus in two years of owning it, and I've dropped it on my concrete garage floor a few times. Cases were unharmed, as well as the phone. Admittedly, the case is minimum protection, so certain types of falls are going to damage the phone. My wife had a Product Red leather case on her 6, dropped it in a parking lot of a mall and really tore up a corner of the case, but the phone was unharmed.
Which brings me to a con of the leather case: it can be damaged and unless you can live with a chewed up looking corner of the case, you have to toss it. With the silicone, it doesn't get harmed as easily.