That is very interesting.Although testing a larger floor standing speaker with the port at the bottom rear and firing into a corner would have been more likely to show up problems with ported speakers.There are a lot of speakers like that and in my experience they are far more likely to cause problems.
Also drivers that can be used in both ported and sealed enclosures of the same volume are not very common .The lower Qts ported ones usually require a much bigger box.
The comments about the larger sealed speakers having better sounding midrange also ties in with my experience.So porting impacts on a lot more than just the bass quality.Having said that speakers using larger diameter shorter excursion ported woofers seem to be much less afflicted by porting than small diameter [say 6-7 inch] ones.
It was clear to me after listening to a few sealed speakers. Listened to a few sealed ATC'S and the difference was quite profound but in the end settled for KLH. That's about much science I applied .... Well, just using my ears. None ported speakers I concluded are much better suited for different room types as suppose ported ones.
If space is not a problem then ported may just seem the preferred Choice, but unless you compare but topologies in your listening environment you may never know.
Bass reflex increases the sensitivity, is easier to drive and provides more extension.
When tuned for higher amplitude (underdamped) it will produce a "woolly", less "tight" or crisp "bass" and is more difficult to integrate(position) in the room.