These happen regularly:
I open Evernote, click on a note and nothing happens for half a minute, only an empty screen is shown.
Notes fails to sync: I edit my shopping list on iPad, 10 minutes later at the store it is not visible on my iphone. Half an hour later it syncs, but it is too late.
For these reasons I will not renew my subscription, a premium product should perform the basic functions flawlessly. (Like many products Evernote suffers from feature creep - the app getting bigger and slower, basic functions are compromised to get more eye candy, etc....)