Chinook is a little harsh for my taste. I do an Arrogant Bastard clone with Columbus that I really love. Recently I went with Tasty's recipe and used Chinook in place of the Columbus. While it is still a very good beer, I prefer the Columbus version I came up with better. Chinook is very present on the finish, whereas the Columbus is more up front with a malty finish.
I really enjoy Simcoe and have not tried it with Columbus yet, but that is definitely in the plans for a future brew. I'll use the Columbus for bittering and the Simcoe at 15 minutes and in dry hop. Probably with MO and a dash of light crystal malt. Should be a great sessionable beer.