Most importantly, KSK is VERY different from just about any music
I really can't compare it to anything else, not even her other albums. While there was a certain progression from Muzai Moratorium to Shouso Strip, this had a different sound, it defies genre.
So I wouldn't really compare; let KSK stand on its own. I'd go for SS first since it's more sonically adventurous than MM was. Basically be prepared for guitars, they are prominent on those two.
All in all I don't think they're "worse" (SS especially) since they're so hard to compare with this one. They're still great music and that's what counts.
BTW I'm surprised this record is an instant love with people, I always thought it's a bit of a tough nut to crack. But that's only good