Well, both Spirit and Opertunity (do not know about Pathfinder) have gone FAR beyond their predicted lifespan. Let's hope that the same happens to Curiosity!
P.S. We will always remember you Spirit! Rest in Peace!
Also, Spirit is not actually damaged. The sole reason it does not function is that it is out of power, and is stuck. If we do colonize Mars. We can go, pick it up, recharge it, and it would still work!
I am just waiting until the Government begins to fund the Ares mission again.
If you do not know what Ares is, it was a mission to put a colony on Mars.
They actually built one of the two ships, started the other, and started training the crew for the mission! Then it was canceled by the government.
Along with all manned flights.