Professional
Great stuff!
Pros: This is the best rosin I've used to date. The bow contact and clarity of sound is superb. Harmonics ring out effortlessly. This rosin has been a game changer for me. Yes, It's expensive. I used to have 2 re-hairs a year, now only once a year. It's already paid for itself in just over a year.
Cons: Not much. Care needed not to apply too much. Not sure about the value of the attached spreader.
Other: Is there better rosin out there?