I can't speak to Oregon's system, but we have this in the Seattle area and I think it's great! Once you know how the numbering system works you can almost always find a house with no information other than its address. We bought a map of the area when we moved here 21 years ago, and didn't buy another until two years ago when we had to doordrop campaign literature in a very rural area (the system can break down when the only access route twists and turns).
Which always seems to happen to me, whether it's Seattle or Vancouver... --------------------------------------------------------------------------------