It's no bargain.

That's the judgment of congressional investigators after a close look at the Defense Travel System, an online system that was supposed to save big money on travel costs.

A Government Accountability Office report says that after 10 years and almost $500 million invested, the Pentagon has a dud on its hands.

If all this sounds familiar, it's because it was reported recently on another GAO report slamming the system.

The new report goes even further, saying the Defense Department is claiming cost savings that it cannot prove.

One example: Pentagon officials claimed millions of dollars had been saved, but the claim was based on a news release from a credit-card company.

Not hard facts.

If Republican Sen. Tom Coburn had his way, Congress would kill the travel system.

Coburn said: "It will take 200 years to ever pay back the cost of this contract in terms of savings, especially when you consider they're not getting the best price."

The Oklahoma senator and other critics say the Defense Department could get cheaper airfares by using discount travel Web sites such as Orbitz or Priceline.

The critics also say that many Pentagon personnel do not like using the system for booking travel including hotels, and that many call a travel agent to buy tickets and make reservations.

Not true, say defense officials who also told ABC News it was easy for anyone to use the travel system to make travel arrangements.

The travel system's future looked bleak four years ago when the Pentagon's inspector general recommended abolishing it.

But Congress continued to fund it.

Both the Pentagon and the company that created the system, Northrop Grumman Mission Systems, say it is already making big cost savings.

Darryl Fraser from Northrop Grumman insisted: "This is a program that the American taxpayer, the Department of Defense can be proud of. It is actually being deployed. It is being used, and it's going to save the Department of Defense money."

The company says the Defense Travel System is being used by more than 50,000 personnel every day.

But the new GAO report says the Pentagon's claims of savings "are not based on reliable data and therefore it is questionable whether the anticipated savings will materialize."

Coburn says the new report only confirms doubts he had earlier this year when he said it was time to halt the travel system and find a better system.

"There are other systems out there. There's a better way to do it. We should not perpetuate this hoax on the American taxpayer," he said.

Coburn found some support on Capitol Hill to kill the travel system, but not enough.

Having already put hundreds of millions of dollars into the system, Congress is reluctant to declare that money was wasted.

Also, funding a new, alternative system would be expensive.

So, it is highly likely that President Bush will soon have a bill on his desk for signature that will spend an additional $60 million on the travel system.