For the most part I've gotten away from the whole "sky is falling" type stuff, but it depends on what you consider to be SHTF. I'm a cancer survivor, so I consider that a personal SHTF because it changed my life forever and it was a very difficult situation. I'd say anything close to a year would be considered long term. I only store about 3-4 months worth of food and water, but I have the skills, tools and knowledge to resupply if needed.