I don't listen to any of these straight on looking down the throat of the waveguide.
Keep in mind that I've heard hundreds of DNA-360's and DE250's at the same exact volume for a year. When I first hooked up the BMS I could hear the difference between it and the other 2. That was before looking at the screen. At first I thought the BMS had a stronger low end just by the way it sounded. I was able to pick up on the difference pretty easy. I listened to it for a while and could tell the lower frequencies were stronger than it's mid frequencies. You can see this in the response. It does not sound bad at all.
To get a better comparison between these, I would listen to one for a while (yes, just the standard test tone over and over). Then quickly switch to the next and adjust the volume by 2db to level them out.
With no crossovers being used and everything at the same listening volume, the lower frequencies on the BMS sound just like the 250 and 360. I can hear the frequency dip from 5khz to 15khz on the BMS. But one reason is because I've been hearing the flatter DE250 and DNA-360 for so long. Of course the dip is the main reason why the lower frequencies stood out more in the BMS when I first started listening.
In real world comparisons, and after a crossover was used to level the DE-250, DNA-360, and BMS-4550 to the woofer, I do believe these would sound pretty much identical in their lower frequencies. Yes, I can hear the dip in the BMS, but no one listens test tones.
And anyone doing the crossover work on would be shooting to level everything. So in the end, they're all pretty much the same.