There are different angles at work. One is the sharklets. However subtle it should make some difference during flare and touchdown from winglets. It did to 747-400 from classic, the 737 guys may opine about the 737-300 and NG. The other is engines.Between the CFM and IAE engines Ceo aircraft the IAE has more thrust at lower levels while CFM has higher thrust at higher levels. This is born out by OEI ceilings which are noticeably higher for CFM. That includes residual thrust. I know of one Airline where they find hard landing occurrences are much higher on the Neo with CFM but they are comparing with their CEOs which have IAE. The Neos have higher fan diameter and higher weight and they feel it tends to drop when thrust is closed. And yet according to Airbus the Neo deceleration is less as compared to CEO. So the correct answer can only come from the Airbus. Can someone get it?