I also have a STX groupset on a Merida Redskins but in this case everything is working OK for commuting, so no need for changing components for now. Thanks for the advise. The 200GS might need the same modifications as you described.I swapped an STX hub from a 7 speed to an 8 speed freehub. The new freehub was an LX one. I think the dishing was ok, but I had to modify some of the spacers on the axle.