Just getting back on after a few days.....have a few things to add
You can have a 125k mile 05 r1200gs and if you did not ride it hard and put it away wet it should be reliable. However if you ride the way I do where dust and dirt gets into everything and keeping it spotless is impossible then reliability due to simplicity comes into effect. I had a early oilhead once and I spent more time fiddling with the motronic and plugging and unplugging the O2 than I would care to admit. Once a wire shorted and I had a harness fire in the 10 miles of wiring that was it...I went back to simple.
I think it comes down to if you ride you bike as designed the reliability is revealed. If you put 100k+ highway miles on your GS and say it's reliable you have no argument as the GS was designed as a dual sport.