I think riding style, and all-up weight contribute to the liklihood (or not) of hub failure. I'm not sure the quslity of rear wheel building affects hub life.
I have Swallow hubs on two of my tandems. The pair on the Swallow tandem have done some 20,000 miles, and the pair on the Claude Butler have done about 15,000 miles. The former used for heavy touring (cycle camping), and the Claude for long fast Fleche and similar rides. The bearings are press-fit and replaceable, though having regreased them once a year with decent grease so far the spare bearings are still unused.
The Sun Wasp is using Mavic solo hubs (36/36) carefully built, with Open 4 rims and 25mm tyres pumped up very hard. They've been used for racing (on the Claude) in the past, and having now covered some 8-10,000 miles.
Rider weights are 13 stone (me) and 10 1/2 stone (stoker), and we don't usually potter!
I do still have a spare pair of Swallow hubs - can't remember spoke count, but likely 40/40. If anyone's interested, let me know.
Does anyone know if Suzue tandem hubs are still around - just curious.
Chris