I have a room with a very low ceiling; I could not get bass to even out.
Here’s what I did:
I went around the room with low-band pink noise playing and, using a db meter, I measured all the places that I was getting very high reading. I called @ethan_winer and we discussed room dimensions and the places in my room where I mapped bass collecting. He suggested two larger and two smaller traps. I purchased them.
In the meantime, I also acquired other bass traps -- corner traps and the taller rectangular ones -- from GIK. These were gifts but I already ordered the Real Traps.
I experimented extensively with placement -- of various traps. The Real Traps were (a) most effective and (b) all I needed. The other traps were not nearly as good.
Real Traps are simply better.