I have ordered from Johnson Strings a few times. For my most recent order, they forgot to let me know that my order shipped and therefore also did not give me a shipping number. I emailed them a week after my order to ask whether my order had shipped yet or when it would ship, at which point I was told the order would arrive that very day. Everything in the package was as expected except that one of the rosins I ordered was very cracked. JSI contacted me the day after I complained to let me know that they are replacing it. Although I am disappointed by their failure to let me know my package even shipped, this is the only time it has happened so far out of 5 or 6 orders I have made and their customer service was responsive and prompt each time. I suppose I would still give them an overall 5 stars given both problems with this order were resolved promptly and my other 5 or 6 orders have gone fine.
Also, their "Adjustable Musician's Seat" cello chairs have been my favourite chairs for cellists for some time. I highly recommend those for cellists and harpists.