Best room treatment

Bottom line I ended up with different brands, and they all work together just as well as a single brand. And that way you get more and maybe better options.

From my own experience, I started out with GIK. Some of their recommendations were spot on, like bass traps in each corner but I opted for the limiter versions (doesn't absorb anything over 500 hz) which I don't regret at all. However their recommendation for strictly  absorbing panels on first reflection points did not work for me. Overall IMO they oversell absorbing over diffusing for a listening room. After adding many diffusers I finally found the perfect balance to my ears between a dead room and a live one. Trial and error will be inevitable no matter who recommends what for you. Check out my system to get a better idea of what worked for me. I ended up with 72 sq ft of absorbing panels and 84 sq ft of diffuser plus the floor to ceiling bass traps in all 4 corners. Have fun figuring it out. The journey is totally worth it.