In powder or on groom? If in powder, where and what was the moisture content?
Fresh powder that was run over by a groomer - groomed powder.
Off trail, the fastest I've done is around 50mph. Snow set for a few days, pretty dense, temperature a little below freezing.
planes really well; 33cm tip/tail width, 28.6cm waist. I often have not-so-steep powder mostly to myself, since everyone else is going too slow to have much fun...