I’m no superfit XC racer but I’ve managed it in under an hour last summer on my charge duster. I know this as my wife was having a cup of tea waiting for me in the cafe with a stop watch. That was with 2 quick runs at the top section
Normally I ride the nomad so would expect to be 5-10mins slower.
I also disagree about it being harder/rougher – I think the climb has got quite a bit easier (still a real challenge to get all the way up without dabbing)
50-60mins should be easily doable – I have a gps now so will be interested to record the times this summer (I expect to be slower as I have half a stone to shift from a broken collar bone over winter)