My friends and I do not find the NF to be fun at all, admittedly the couple times we tried we were not very successful but in the past we would have kept playing to learn the path to success rather than just decide to not do them. I would not say they are overly difficult, they are just not fun. Run and gun stress added to content we already play is just kind of lame IMO. Some people may enjoy it but my friends and I would rather concentrate on the raid and just forego jumping through hoops or Sparrow riding past mass amounts of enemies all for the sake of beating a timer.