I'v used vivosun with my first grow, now i just use it in my drying room(4 and 6" combos) Up graded to a Fusion Breath 6" system with their biggest filter last year and have been very happy with it. It is very large though. Heres the most important part of buying a filter..make sure its big enough for you fan output. For example, if your fans maximum output is 400cfm..make sure you get a filter thats rated for 450-500cfm or higher. that way you cant overload your carbon filter. I notice with alot of these combo systems..they are rated for the exact same cfm..and if you have a stinky tent they just cant keep up.