21st Street Coffee is an interesting place to say the least. A more appropriate name for the business would probably be "The 21st Street Coffee Experiment".
Let's make one thing clear: this is the best coffee in Pittsburgh. Luke (the owner) undoubtedly knows a ton about every aspect of the coffee making process and they produce a product far superior to any coffee shop in Pittsburgh.
Where 21st Street Coffee consistently falls short is with customer service. They are not interested in what you want, they are more interested in presenting their product to you in it's purest form. They are on a mission to convince people that great coffee should not need any additives. While this is an admirable cause it is extremely alienating to people who are used to a routine or for whom coffee serves a very utilitarian purpose. Most people don't want to feel challenged when they go to purchase their coffee, especially early in the morning.
If you are going to visit 21st Street Coffee, go in with an open mind and just go along with their suggestions. Your coffee will undoubtedly be amazing. Go if you want to treat coffee as a delicacy. Don't go if you are in a rush because the service is slow.
This review could easily be 5 stars if 21st Street were to abandon their "one size fits all" policy towards customers and start serving their customers needs rather than their own objectives.