hmmmmm maybe this is the reason why Huawei plans to use glass casing for p7.
If P7 comes with some kind of scratch proof glass material, it would be a killer feature.
Anyway to answer your question, i use a slim casing to be on the safe side and not have the horror scenario of seeing a scratch on the phone. Because it is a slim casing i haven't sacrificed too much of its original slimness.
You could on the other hand buy some kind of pouch type cover so you can use it without the pouch whenever using.
Huawei Ascend P6-U06 (EMUI2.3+KitKat)