This Starbucks is in very close proximity to my work so it is the one that usually go to by default. It is just okay in terms of customer service. I have had good customer service and bad. Today I remembered that I needed to get a cup of ice water after I had ordered my drink and I politely asked the barista if she could possibly get me an ice water along with the drink I was waiting on, they were not busy at this time so it really should not have been a problem and usually isn't at most Starbucks. Today the barista seemed quite irritated that I had asked for water after ordering.
I have also had good customer service with one of the cashiers personally bringing me out my sandwich on a plate. I thought that was such a nice touch and very unexpected for a Starbucks! Overall it seems like it really depends on who is working and what kind of service you will get will vary. I will still come back because apparently I like paying ridiculously high prices for mediocre coffee.