There are professional studios and producers using the SV9s for monitors and the reports we've heard have been very positive. We've had many phone conversations with folks that indicated they were very happy with their MK2 SV9s in their studios.
The MK3s are even better. They have a lower noise floor and higher output. The lower noise floor is the biggest benefit for studio use and higher output is not usually a bad thing anywhere...
The SV9 MK3s are very good speakers. It's difficult to understand what they will be able to do for you until you have them, but once you do, you'll know.
The intention of the SV9 MK3 is to make your creative work easier and more enjoyable, and thereby better. Adding more steps, wore work and more processing doesn't serve that purpose and we do our best to provide products that need nothing more than power and signal.
The SV9s will make your efforts in the studio easier by providing you with high-resolution referencing, and it will make the sharing of your efforts easier by translating it to larger audiences and spaces without changing the fundamental character of what you've done in the studio. In other words, the engineering behind these systems is intended to make it possible for you to play music rather than work in the studio or work on a show.