Here are the two S. alpina I bought from the Dan Hinkley collection. (And no Ron, I didn't pay as much as I did for the Sinopanax formosanus, about a third of the price.) According to people in Europe who were growing this during their 2010 winter with temperatures down to -12°C for several weeks, they made it through that winter just fine. So should do fine in most of Western Washington and Oregon, along with the islands in British Columbia.

I think they are very attractive with their evergreen dark green leaves, almost as much as Schefflera taiwaniana that is starting to become common in NW nurseries selling Monrovia plants. Dan Hinkley says they need fast draining soil, which makes sense since they live in the mountains. Another Schefflera, S. brevipeduncula, that Dan sells through Monrovia I found out the hard way also needs fast draining soil. I put rotted steer manure compost around a plant, the bark, where the compost touched it, and the roots rotted killing the plant. I thought it might have been the cold, since 2008 it got to 17°F at my place, but two others planted nearby without the compost made it through that winter without any signs of damage. Also a friend of mine did the same thing and lost his. That's something to remember when growing these plants. With S. taiwaniana and delavayi I got away when treating them the same way, but I stopped adding compost to them after losing that plant. It's a learning process.