I have not had the chance to take an in-depth look yet, but the CBO gives Rep. Ryan's "Roadmap for America's future" an optimistic rating:

The budget deficit would peak at 5 percent of GDP in 2034 and then decline. By 2080, the Roadmap would generate a budget surplus of about 5 percent of GDP. Under the Roadmap, the ratio of government debt held by the public to economic output (the ratio of debt to GDP) would be lower than that under the alternative fiscal scenario in every year. In particular, debt is projected to peak at 100 percent of GDP in 2043 and to decline thereafter, reaching zero by 2080.