What could possibly be so valuable about Mars to warrant such an expense?

Instead of crashing the skycrane, why not put a camera, microphone and a wind speed and direction instrument on it and attempt to have it do a controlled landing?
It'd be stationary but it'd be a useful scientific instrument package instead of a single use device.

The discovery of life on another planet? Sounds valuable enough to me. The Expense? About $357 Million a year over 7 years. Or about.....$1.19 for every citizen in the USA per year.

A very big mylar bag, inflated prior to reaching Mars, would allow visual tracking from earth and would act as an extremely big parachute, enough to "stick" to the Martian atmosphere and ease descent. Inflating other bags inside the big bag(s) would assure easy touch down. NASA's Rube Goldberg wasteful system derives from an imbecile's exploration paradigm. You don't decide what to look for from Earth. You go to Mars and look everywhere. That means multiple, cheap, inflatable rovers all over the planet. Hopefully, exploiting some native power source (e.g. the Martian wind).

"The landing sequence will start at 13,200 miles (21,000 km) above the planetary surface, and will last only seven minutes... Hitting the atmosphere at 13,000 mph..."
How is it going to land in 7 minutes from over 13,000 miles altitude if it is traveling at 13,000 miles per hour?

You don't consider the possibility of finding alien life on another planet worth the effort???

Name any form of life that can exist without the basics which support life. Now name any place in space that has all of the provisions to sustain life. It is sometimes called the circle of life. It just does not exist. When attempts are made to find this imaginary life - it reminds me of a dog chasing his tail.

everyone misses the point... IF we find ANY life on mars at all, in any form, in any way, etc. then mars if OFF LIMITS for the whole human race forever! we simply can not risk any kind of alien organisms/pathogens to be brought back to earth...

Then Timothy, wouldn't it be cheaper to just leave it alone now? What is there to gain by confirming there are no Martians?

I want to see this because it looks freaking AWESOME! Although it has a very high "what could possibly go wrong?" factor, I think it is a super worthwhile project.