iOS 8 beta is definitely best avoided for now IMHO. There are just too many bugs which crash my iPhone 5 for me to recommend it. A few examples:
1) who would have thought that pressing the Settings button would crash the app (after switching on the phone from off)
2) Battery life is shocking too even with just a single app running. I've followed all the recommendations that are supposed to help but no joy just yet.
3) Unless you are a developer then there is no support
4) If you try and select multiple mails, to move them to a specific folder, the select button disappears once you scroll down so you have no idea of what you have selected.
5) If a purchased app stops working after installing iOS 8, there is little or no support from the app developer.
Obviously these are just the first 5 that popped into my head but I'm sure I could list more!
I'm tempted to roll back to iOS 7 for now and upgrade when it's a little more stable. It's such a shame that there are too many issues right now but once the fixes are in place it will be fab. Please, PLEASE Apple, address the battery life issue first... Or maybe start sorting out the crashes first...