General Motors Corp.'s latest debt-for-equity swap proposal is barely out of the box, and some critics already have declared it a non-starter.

GM wants bondholders to exchange their $27 billion in debt for a 10% equity stake in a restructured company. They’d get 225 shares for each $1,000 face value of debt.

By contrast, the United Auto Workers’ retiree-medical fund, the Voluntary Employee Beneficiary Assn., would get up to a 39% stake in the new GM in exchange for forgiveness of at least half of GM’s obligations to the fund.

Some analysts say bondholders can’t help but see the terms as a raw deal for them. [UPDATE: See the official statement from the bondsholders' ad hoc committee here.]

In a report today, Barclays Capital analyst Brian Johnson estimated that bondholders ultimately would get between 0 and 5 cents on the dollar if they accept the latest offer (after accounting for stock dilution from the issuance of new shares). The UAW, he estimated, would get between 50 and 60 cents on the dollar