For me, most of the appeal was the fun/challenge of doing it. PJ's solution is extremely clever (for example, one switch can "throw" a wire to either an OT terminal or to a pole of the second switch, which in turn can "throw" the wire to 2 different OT terminals, providing 3 different OT terminal connections for the same wire; another combo of switch positions achieves something even more elaborate). It really is (to my mind) an ingenious use of two DPDT switches and it was quite satisfying to appreciate the cleverness of PJ's solution and then build and install boards that successfully implemented it.
Sonically speaking, I suspect the switches are at best neutral and possibly a detriment. The switches require a bunch of additional signal wiring right next to the OT and only a short distance from the PT (b/c in the SII, unlike in the Kaiju, the OT terminals face inwards toward the PT) - and even if neither has enough flux leakage to impact the signal, the additional wiring makes a larger "antenna" for possible RFI. I recall reading a statement of John Camille to the effect that all wiring is a potential antenna and accordingly wiring should be kept as short as possible. I shielded the additional wiring in copper braid (which took forever and resulted in a bizillion wires to chassis ground), but I still regard the switches with some suspicion: "Are they hurting my sound?"
But they were fun to make.
cheers, Derek