SB, SD and NS2000 are all wonkier takes on the original NS, just far uglier due to the lack of good design ethos. Even the NSX is a clumsy clone of another famous NS design isn't it? Again far uglier that the sleek, on point shape it's copying.
They truly are the Behringer of bass when you think about it, not an original idea in 45 years. That's actually impressive in a weird kind of way, you would think they'd have come up with something half decent on their own purely by chance sooner or later. You know how a monkey sat at a typewriter could theoretically write the complete works of Shakespeare given an infinite amount of time? You reckon if you did the same with Stuart Spector he could eventually come up with a bass that didn't look like total a55?