Not sure if this has been mentioned before - but its a starting point.
http://www.bikeme.tv/Writings/tabid...Id/303/THE-ESSENTIAL-BUYERS-GUIDE-BMW-GS.aspx
from amazon here : http://www.amazon.co.uk/BMW-GS-Esse...=sr_1_1?ie=UTF8&s=books&qid=1213242228&sr=8-1
http://www.bikeme.tv/Writings/tabid...Id/303/THE-ESSENTIAL-BUYERS-GUIDE-BMW-GS.aspx
from amazon here : http://www.amazon.co.uk/BMW-GS-Esse...=sr_1_1?ie=UTF8&s=books&qid=1213242228&sr=8-1