I'm happy to say that in 4 years and 40,000 miles my van's only let me down once, and luckily I was (barely) within cellphone range. This was a fuel pump failure in rural Oregon -- but I've already posted about that.
The only other major roadside failure I can think of was when a hub popped out of place at the 2006 Sportsmobile Rally in Colorado. Heber of Sportsmobile West was kind enough to repair it right there, and new updated hubs were sent to me soon afterwards.