True Google doesn't have offline navigation which isn't great if you're roaming and can't use data cheaply.
Not true. A few other navigation app efforts were sorting out map caching, so Google pretty much had to join in. Check your settings for options.
I haven't used it yet, but it's there.
You can cache the map but you can't get directions unless you have a connection. I have been finding having the map cached does make it run faster though.