Hmmm... does not look very heat-conductive to me.
Almost sure AS-5 could do better... One note of caution though... The chip has plastic cover, while AS-5 usually sticks to metal cover of CPU's IHS.
Metal IHS is probably more flat compared to plastic top. So the micro-gaps are probably bigger on the plastic top, so for the plastic top I would be putting just a bit thicker layer of AS-5, compared to what we put on CPU.