> Anyone have/use GB Syncron brakes? Any opinions about them? Good bad or
> otherwise? Any notion as to the date range these calipers would be
> appropriate for?
To the best of my knowledge, these were actually made by the Swiss company Altenberger. There is a set currently up for sale on ebay: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7106885572
They are actually quite good brakes and far better than the price on this auction would indicate. I picked up a pair myself. Under Altenberger guise, they were used at least as far back as the 60's. Look in the archives for more information about them.