I bought the 1 0z. bottle on ebay (the seller was Korber Models) a few months ago and, after experimenting with various other methods (some mentioned here), I found the Robert's to be the best for the new Roundhouse I assembled. No adverse smell and worked as advertised. I brushed it on and let it set for about 30 - 45 minutes and then wiped off the excess and was satisfied with the results.
I wonder how long yours might have been sitting in that hobby shop's inventory.