What are Nerdarchy's thoughts about West Marches campaigns?

Matt Colville recently made a video about a style of game called West Marches that's been circulating around the various DnD subreddits lately (link for the lazy https://www.youtube.com/watch?v=oGAC-gBoX9k). It sounds interesting to run and with my schedule and responsibilities may be something i want to try. Does anyone have any thoughts or experience running that kind of game? What should I expect and prepare for if I try to set one up?