As I recall some of the lessons we’ve had from Headmaster Shady, driver and cabinet design, port tuning, group delay... All of these contributed early on to the creation of that myth. Most of these problems have been left in the past, now. With any of the companies we typically discuss.
It seems that when you move beyond that story, what you are left with is deciding on the FR and output profile (infrasonic v. Mid-bass), then the size and connectivity/UI options.
Other than matching Sub to room size, which includes sealed subs for rooms below 3000cu.ft, or support for large and extreme rooms, there is very little left to worry about.
In the end, the outliers are subs that have not been handled in-depth for third party tests. At this point, that is newer Rythmik and PSA subs. There are some older reviews of Rythmik on DataBass. If anything has changed with them, I can’t say.
But what I can say is that I would not use sealed subs unless I had a room smaller than 3000cu.ft, and be able to employ 3-4 in the room. Even still, my 2 porteds perform very well in my 2000cu.ft. room. Even
@CB22 found the outlaws to perform well enough that he moved his old Hsus out iirc.
In the end it’s all about setting the subs up right in your room. If you get that done well, and you have a sub of solid quality and performance, there should be no musicality concerns.