QUOTE (southsider2k5 @ Oct 28, 2010 -> 12:32 PM)
That makes absolute sense to me. I also agree with the "lose it" part being exactly why I have never signed up. Any money you don't spend is a 100% loss, versus whatever you would save on taxes. Unless you have significant and regular expenses, the plan doesn't make a lot of sense.
I believe that is part of the rational for the program, it isn't for everyone. I have maintanance meds that I take every month, so calculating several hundred dollars is easy. The use it or lose it wasn't so much a bother as long as I could load up on OTC in December. I'd replenish my first aid kit, pick up some Advil or whatever, maybe some cold meds.
Basically I added up a couple Doc visits, meds, annual physical, etc and put in a little less than that.