I grabbed a diztronic or whatever case and it's awesome. I got over the sandstone back in a day. It feels nice at first, but I was afraid of touching it because it just shows every smudge and stain, mostly from your hand oil.
I was originally using the oneplus flip cover but have since changed to a Tudia case, much better fit and protection. I got an official case for my gf and it didn't even fit the phone :/ She also has a Tudia now, perfect fit.
This is the one I have:
