Wow, that's really cool. I just added one road that was missing in the neighborhood.
Yup. For small edits, this is perfect - it's in-browser, well integrated with the default map, plus it has a satellite layer by default :)
iD is fine for lots of edits. It's only when you what to lots of complex things (like relations, administrative boundaries etc) that you should break out JOSM
(As for me, I prefer jOSM - more complex, Java-based, not in-browser; more powerful in various ways: https://josm.openstreetmap.de/wiki/Download )