Leon, I agree. To me progress in gliding is a Silver C (5 hours duration, 1,000m height gain, 50m XC flight in 3 flights or fewer), followed by Gold & possibly Diamonds. However on the day I did my 50k I could have done it in a Junior, which is pretty similar performance to the Vikings. The point really is going well out of glide range of home, though some Scottish 50k flights in wave are in theory never out of glide range!