Windows phone is stable and always has been, unless on the preview for developers and using pre-consumer release software there abound to be some issues and bugs.
When you get the Lumia 930, I would suggest you get the following apps
1) Windows Central for the latest news about updates, apps, PSAs etc.
2) MetroTube or Mytube for youtube (MetroTube is a donationware app with an unlimited trial).
3) Simple Calendar, Cal or Chronos Calendar
4) Skinnery themes for custom tiles and shortcuts.
5) file manager first there are plenty of decent ones in the store I.e aerize, pocket explorer, files.
Sure you can do without a file picker or manager however there are a few quirks that you need to be aware of, namely attachments from the email hub defaults to the Photo hub, to attach documents you need to use the share function in the office hub however you can only attach one document as attaching any subsequent documents directs you to the photo hub. The only way round this is to use a file manager or file picker if you don't want to use cloud storage to share links to documents.
Another quirk is the music apps or now playing bar doesn't have a stop button, so you will need a app for that (I use stop+clear).
Also the Wi fi toggle works differently, tap once to turn on however tapping again doesn't turn off but loads the Wi Fi settings page where you can choose if you want to turn it on manually or after a set period.
The shortcut bar in the notification centre doesn't have a cellular data toggle, you can use skinnery ro create a shortcut or grab one from the store.
Lastly the unread counter on the pinned tile disappears once the app is open regardless if you read the message or not.
One aspect I love about windows phone is offline maps, download the maps once via Wi Fi thus saving your cellular data allowance.