Which brands work the best for the iPhone 6s?

[iMore Question]

iphone 6s battery cases

I have had the mophie but I don't like it because the switches don't connect to the phone very well.
I am considering:
-Supcase
-Phonesuit
-Trianium
-Spiegen
-Anker

Do you know which brands' switches work the best? Also, which of them can you turn on/off?

 

[BreakingKayfabe]

Re: iphone 6s battery cases

The Apple Smart Battery Case for the 6S is the only battery case I use.