I know first-hand the Ledn model and I think safe to say that the overall amount of interest you'd pay will be much less with Bold. Main reason is with Ledn you take out the entire amount of your loan and start paying interest on it from day one.

With Bold, you can spend for a month and then at statement time decide what you want to pay down. If you pay it down completely, you pay no interest. But even if you carried the entire balance, it's only after that month that you being accruing interest.