I personally am not a fan of rest days. I tend to ride every day at home and on tour. I might take easy days here and there on tour. I sometimes call them half days. That said If there is something special I want to do on tour I may stop for that. That might be an all day hike, whitewater rafting, or whatever. Once I took a a week off to explore the Yosemite Valley, but regular rest days are not the norm for me.