I keep all my outdated flairs in my ditch kit and when I use one which was 5 years ago I used 5 before the boat that pulled me out from 5 feet from the rocks saw one becouse it was daytime the four old one's came in real handy that day.
I agree. I do the same. Correct me if I'm wrong but I think you can still have them onboard as long as yo have ones that are not expired. You can use them as back up or whatever. I have been told 90% of the time they stay good well past the expiration date.
Let your family, and the friends you go out with practice. Only keep top notch safety gear on board. If something goes seriously wrong and you're 100 miles out, you'll be glad you have everything in order.