Well! My new GSH2's have arrived and they are very different to the ones I had from Amazon which were always leaking.
They are smaller, and have the scale set into the plastic rather than printed on. Also, the inner tube is smaller. Can't fit a cotton bud into it.
I am now confused about which ones are fake 
I went for colour in the end in the hope of a nice blue or purple but no - red, yellow and grey 