I haven't used it without my phone present yet but yeah - once a route is synced you no longer need it.
Maps for pretty much the entire world come preloaded on the device, with something like 100MB free space. I deleted all the maps except for Europe and now there's over 1GB of free space on there.
They're OSM maps, yeah? As OSM gets more detailed is the unit going to struggle with storage space? I have a lot of store routes on my Garmin for example and can just bash in an SD card. Does Wahoo have an SD slot?
I guess that might work, I didn't know about that. Might wait until I've got some longer rides planned though. God, do I really want another system?
Once the route is loaded onto it, does it need to talk to the phone still? I don't want to run Wahoo and phone at the same time.
Do they have maps on-board?