I had mine replaced recently (again) - with a genuine (again) - the installers always comment how much heavier the genuine on is compared to aftermarket. But they did comment that there was no bond along the top edge between the screen sealant and the bodywork - he was able to put his knife straight up through the gap when he was cutting the bond (or lack of) for removal - no wonder she leaked every now and then. So yes - lots of sealant at the top and push the bugger hard when fitting.

