I personally think Philz is going to give third-wave coffee a run for their money. Definitely as approachable as Starbucks and easily replicable. The problem with third-wave is that the total applicable clientele for a company like Blue Bottle is far and few between. Even after saturating every corner of SF, NYC, LA, Chicago, it's going to be hard for BB to come up with hundreds of millions of revenue and retain quality (Blue Bottle raised $100M in cash). Blue Bottle has a "luxury good" perception.
Philz is unpretentious, reliable, and love in a 600-calorie cup of coffee, cream, and sugar. It's a formula that so far has proven to work in America. Third-wave coffee is excellent, but isn't as accessible as Starbucks. Philz, on the other hand, doesn't attempt to sell the virtues of high-brow single-origin coffee. They, however, make a really good cup of coffee, and reliably do at each location. I definitely believe it is repeatable even at scale because many Philz drinks rely on mint leaves, cream, and sugar--flavors that are the "MSG" of coffee.
User experience is inclusive and welcoming--although some locations are more fun than others (visit the 24th if you haven't and it will become abundantly clear why there are Philz phanatics). I love coffee shops like Four Barrel, the Mill, Saint Frank's--but those shops exude refinement and appear a little out of reach, even if priced similarly to Starbucks. I would hypothesize you could put a Philz in the Midwest and it would do well.
As of right now, every coffee shop compared to Starbucks pales in comparison. Starbucks boasts $70B in market cap. If anyone has a good shot of picking a fight with Starbucks, it just might be Philz.