I'm new here (at least new at posting), and $2-$3M group seems to be where I am. I was on that traditional retire at 65 path, and really course corrected about 3 years ago after googling "How much is enough" and discovering the FIRE movement on the internet. I'm 52, working as a mid-level corporate manager, and my wife works in the service industry in Southern CA. I started transforming my life toward Mustachianism without knowing it about three years ago - renting out our suburban house, moving to a 2 bedroom near work, and eliminating a 3-hour round-trip commute. Now I save about 1/3 of my annual income and have liquid investments of about $2.4M. I'm targeting quitting my job in about four years at 56 when our youngest is through college and that large variable is behind us. Though I know I could go FIRE today, we would like to move back to our home community in the suburbs to stay long term, and that isn't exactly inexpensive.
I can't say I can closely relate to the 30-somethings retiring on $40k a year, but I believe these principles can be applied by anyone's situation wherever they are at. It has certainly changed my perspective and direction, and I appreciate reading all of these stories!