Sprint Nav was good for a time. But it's not quite up to Google Nav. Especially not at this point in the game. Last time I used Sprint Nav was about two years ago. Drove me F@$&ing crazy. Was crazy slow to update. Ended up driving past my exit. So for me it's Google Maps/Nav all the way.
The new Sprint navigation app looks nice but I haven't really given it a full test run. One thing I noticed is that it keeps saying "downloading files for first time use" even though it's not my first time launching the app.
Google Nav has been working really well for me...besides when my GPS wants to lose signal due to CM7. But that isn't Google's fault.
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