My painstakingly restored (by me) vintage La Pavoni works well for me with Bluebottle coffee. I think the high temperature of this machine's grouphead and water, suits the darker Italian style roasts they do. For me, Ritual and Fourbarrel are too fruity and not roasted to the point of exuding oils that work well with a long high-temp hand pull. You can see this by simply comparing the beans of each roast visually - Bluebottle's espresso roasts are dark in uniform, sweating oils slightly - Ritual and Fourbarrel's are lighter and speckled with a light streak in the fold between the two lobes. I haven't tried Sightglass yet (and those 4 currently wrap up the top espresso blend producers in San Francisco's coffee wars).
Alongside discovery of all of that, I've been working on my latte art, as the picture above shows. Great coffee is one of life's lasting pleasures, along with many things you ingest and make a part of your body I believe they should be as good as you can get them (economics prevailing). Latte art is just fun though. Here's how to steam the milk so as to get micro-foam for latte art, and a few of the “arts” courtesy of Brooklynshot :)