I remember it being really good, though I haven't read it for awhile. I thought I remembered hearing a podcast where Rob talked about what he would change if he rewrote it today, but I can't seem to find it (maybe someone with better google-fu can)

Here is one of his podcast episodes where he talks about it though - so you can start here: https://www.startupsfortherestofus.com/episodes/episode-219