The review showed that "Amtrak's initial projections of ridership, revenues, and costs for this new system were appropriately conservative," Engel added.
"We are pleased that many of the world leaders in high-speed rail have offered their ideas to help refine and improve our plans," he said.
The reviews are unlikely to mollify Republican critics, who argue that the model of having one national rail company does not work in the United States.
"By focusing on projects that make sense, leveraging private-sector investment and opening the door to public-private partnerships, we can do more with less and finally take our nation in a new direction," Rep. Bill Shuster (R-Pa.), who chairs the House Subcommittee on Railroads, Pipelines and Hazardous Materials, wrote last week in an op-ed in The Hill.
"It's time for passenger rail to enjoy the same success deregulation brought to the freight rail, commercial truck and airline industries," Shuster said.
This story was clarified at 5:45 p.m.