Contradiction
Given that searching for evidence of extraterrestrial life is one of the big reasons for going to Mars you are sort of contradicting yourself. Discovering evidence of extraterrestrial life will be much bigger than landing on the Moon IMO. It's like crossing the Atlantic compared to finding the Earth orbits the Sun rather than the other way around. I'm not saying that will happen if we go to Mars, but that it would be far bigger news if it did. I think it has been our greatests technological acheivement, but not our greatest scientific one.
Regards,
Mark