Might be a good auction to watch. These ones that start at a higher price ($50 in this case) sometimes do not draw as many bids and wind up selling for less.
Yes, interesting auction. The TW-1 SS has never been a top $$$ pedal, much like the PH-1 SS, even though they are oldies.
I own an early TW-1 with black screw and original box, but are also drooling for a SS-version. However that TW-1 was the first Boss pedal that started my collection, so it holds a special place in my heart, silver screw or not.