Well, for the first week of ownership I was ready to send it back. It couldn't do TBT navigation reliably, and despite various people attempting to tell me that I didn't need TBT, TBT is what I want.
Curiously, Garmin issued two firmware updates over two weeks, and this on a device that is well into its second year. A quick perusal of garmin forum revealed a gathering shitstorm of pissed off users all with the same issues as me.
The second of the two firmware updates (beta) has the thing working as I'd like it. So hooray. It has frozen once (boo) and also seems to reset the trip distance to zero if I turn it off and on again. (The 705 didn't). It might be a setting buried somewhere deep, or it might not, but it is bloody annoying in a long audax where I may want to conserve battery life at control stops.
Other that that, its OK. The display is fine, the touch screen works and the Bluetooth stuff is handy.