You'd be hard pushed to find a decent 2 bed flat for rent in the grange or marchmont for less than £800pcm. Good luck finding anything under £1000pcm in ravelston. Leith is a cool place to live with great transport links, lots of bars and restaurants and reasonable rents.
People that either haven't ever lived in Leith or lived in Leith before the late 90s have a dim view of it, but it has been regenerated and is becoming a trendy area to live. I'd totally recommend it.