I can't give you much in the way of help knowing which is better, buy outside or here, as both mine were bought here, but I'm just lazy :-)
It seems that it may be cheaper buying outside, and paying the import tax, but you have to know what you're doing, in regards to if the bike matches the import specs for a swiss bike. They are quite strict on aftermarket add-ons.
Am sure some of the other guys will chime in with more info.
For ideas, can try these in CH http://www.car4you.ch/AppPortal/Page...spx?StyleID=60 http://www.motorradhandel.ch/occasionen-suchen.cfm