I have the Garmin 705 - works fine for turn by turn. I got mine on eBay last year for $300 (refurb)

Also, forget the phone route - been there done that - flattens your battery in an hour. The 705 will go 12+ hours without a charge. Best piece of kit I ever bought for the bike bar none.

Here's the same bundle I got (hear+cadence included) for $300. Highly recommended.

http://www.ebay.com/itm/GARMIN-EDGE-...item45fd307b58