Out of the many search results, ninety percent of them were negative. They detailed drunk passengers, crazy people creating chaos on the bus (including a guy with a pistol in a paper bag), uncomfortable riding conditions, and overcrowded buses. Not exactly the type of stories to reassure you when you're contemplating a 35 hour bus ride.
I figure it will all be all right, though. After all, can it really beat traveling by bus in Central America? Probably not. The odds of getting proposed to or felt up are much, much smaller (much more so on the former than on the latter).
Wish me luck!