Hi Rictose,
For my mind, Sabre basses have only 2 bands preamp. Perhaps some custom orders have three bands and some have not genuine: John East, Seymour Duncan...
I had a 3 bands 92 Stingray and I doesn't often use medium pot, bass and treble a lot.
Today, I've a classic Sabre and it's really an amazing bass. The principles differences with 91 models are:
-6 bolts on neck instead of 4
-Superbes necks finished: flammed or Birdseye with vintage gloss polyester.
-Phantom active coil for silent use on neck single coil
-The 5 way switch isn't wired in the same order
-I forgot, preamp is CMS technology, electric consumer is very low.
I think classic series are the best finishes Musicman can offer.
Excuses my English, best regards from France.