The Sun-Yat Sen Classical Chinese Garden in Vancouver, Canada 

This is only my opinion for what it's worth, but they are comparable. When I say the Vancouver garden, I gained more respect for how exquisite Portland's garden is. The Vancouver garden seems a little larger to me, and has a few more courtyards and corridors. Other than that, the artistry, craftmanship, pruning, plants selection, rock work, and everything else in both gardens are on the same level with each other.