S3X is a lot of fun, I ride hundreds of miles on mine each year, but I don't think I'd want to tour with it. The hybrid gear is not an option on an S3X; it has an unusual driver that will take only one cog. The hybrid option assumes an old AW or similar.
The same hybrid effect can be achieved with the s3x, giving 6 fixed gears. You could use the Patterson Transmission, 2 speed, internal geared crank. No need for extra cogs or chain tensioning devises.
Patterson Transmission Crankset 
Internal planetary geared crankset, compatible with most conventional frames, providing a 1.6 to 1 gear ratio.
DESCRIPTION & MATERIALS
Die cast alloy crank arms, External bearing BB, Two speed planetary system, Achieves 28T to 45T drive gears, Overdrive ratio 1.6:1, Downtube cable routing, 68 mm BB
SIZES
Length – L165mm, L170mm, L175mm
Chainline – 46mm
28T drive chainring
FINISH
Brushed alloy silver
Color graphics
WEIGHT
1730 g (complete assembly including BB)