Oh yeah, for sure you can have exceptional performance from dual porteds. There is just something "ninja like" about sealed subs.
I have done it both ways. Porteds go louder for sure. But man, to have that bass crack you in the chest, then completely dissappear, is really something else. IMO sealed units give the impression of a more dynamic experience -because there is no port lag or drone. Some call the experience "room lock" or sitting in the "poweralley". To get a similar tactile response from porteds you have to crank it loud. I think this may be the "noise" factor byproduct brwsaw is referring to. It gets to the blaring point I guess.
Here is a point to take it home. I would sooner not have ATMOS than go back to a ported setup.
I got the first ported one because I had a large CuFt space to fill, could only buy 1 sub, and needed a lot of LFE power for my $850 that I spent. The port gives you that for large spaces like that.
I then added a "twin performing" DIY sub to try to keep things identical. That smoothed out the room nodes a decent amount, and also meant that I could run both of them at a lower gain than one alone, meaning less air pushing and pulling through the port.
Sealed subs or much more musical of course, and can give a tight "punch to the chest" feel, which is why I am wondering if adding a 3d sub, but one that is sealed, will play well with the others.