Should I upgrade to iOS 9?

I Have recently bought an Iphone 5s gold and it has iOS 8.4 on it currently. As I have read that there are no notification noises when whatsapp messages come through on ios 9.02 I haven't upgraded as iOS 8 seems to be very stable and reliable.

the thing I want to ask is, should I be upgrading to iOS 9.1 yet ? Has this latest release fixed all these glitches ? Any feedback would be greatly appreciated.

Thanks

sean🙂