If I retire now, it would be about 25% of current income.
It's too bad you threw the "25% of current income" into the question. Determing FIRE budgets based on a percentage of pre-retirement income is a hot button here on the
FIRE Forum and the answers you're getting are mostly focused on that percentage rather than on what you're really asking.
We would have to leave California for a lower cost state and tone down the life style. Kids are launched. Our Fire income would be comfortable by many standards, but not compared to our current lifestyle costs. Anyone know of a successful downshift by that much?
I think you're talking about a very personal situation. You gave no detail on how much you're enjoying the high tier Calif lifestyle, whether you have friends and/or relatives there and would really miss them or whether there are expensive activities you'd really miss if you gave them up.
The fact that you've asked the question hints that you do have some concern about moving to a less expensive location and giving up life amenities you currently enjoy. As to whether cutting off access to your current location or those pleasurable amenities would be offset by the pleasure of throwing in the towel on your not-so-enjoyable career, you'll have to decide that.
You might try listing some of the important, relevant issues and think about them a bit. For example:
1. If you currently live in a deluxe home and have well educated, sophisticated neighbors, would it be OK to be in a much more modest home and perhaps have neighbors (and possibly new friends) who are involved in or retired from more plebian circumstances? That is, the guy next door is a retired postal worker or truck driver instead of a retired orthopedic surgeon or college president...
2. If you enjoy any current amenity such as membership at a private golf club, would it bug you to be out on a public course with the rest of the hackers?
3. Do you do anything expensive, such as travel, gourmet dining or live entertainment on a regular basis that you'd miss?
4. It's possible that in your current career you don't have time to do a lot of things for yourself and can easily afford to pay others to do things for you. Will you be comfortable being much more self-sufficient over a wide range of activities? Taking care of your own house and cars, doing your own investing and taxes, whatever, etc.?
This list could go on forever and I only mean these notions to be examples. You have to think about the substantial items in your current life that will permanently go away and decide if the loss will be adequately balanced by not having to work at your current job.
Again, because you asked the question, I'm assuming you have some concerns, that you think there will be things you'd miss and that your job isn't so bad that it's a slam-dunk that leaving is for you.
As far as knowing anyone who has done something similar, I'm afraid I don't. We do have friends who retired from highly compensated jobs (a corp controller and a very successful bond trader), sold their downtown Chicago high rise condo and moved to a hobby farm in Wisconsin. They seem very happy and can't believe how much less they're spending. But, and it's a big "but," they could afford to come back to Chicago, purchase another high rise condo and resume their swanky, urban lifestyle if they wished due to a huge FIRE portfolio. You sound as though your move would be a one way decision which is a very different scenario.
Good luck!