Impossible to get money out in advance for fortnightly necessary meds (spouse has allergies, only one that works for him is pseudoephedrine; there are no PEs on our formulary, so we had to use otc and go through the anti-meth registry every 15 days) or other planned expenses like my spectacles; had to fax (not email scans or mail hard copies) of receipts which meant paying for a fax service (no landline since 2001). Took up to three months to be reimbursed for out of pocket expenses. Required out of pocket income available, which defeated the purpose as far as we were concerned. Our company would lose any faxes sent after 4 pm eastern or on weekends; I got in the habit of calling the customer line, hitting send, then sending my operator check the machine while I waited on hold. (per suggestion from another operator.)
Figure 3 hours a month, so 36 hours, plus $40 for the fax service, for 440 in tax savings a year, all in reimbursement, so we had to bear initial outlay. If we put any of that (I.e. my specs or DH's root canal) on a card and didn't get reimbursed for 3 months, that also means we got dinged for two months interest at around 14% APR. So not worth it.
ETA : we earned no interest on the money; my annual specs are at year end, so we were building up for that. (I'm not cheap on specs, unfortunately.) They probably did make interest. Better for us to take it, take the tax hit, and drop the cash in a 6 month CD.
If the plan has a debit card linked so that there is no reimbursement nonsense, they make sense for things like deductibles, dental, optical and durable medical supplies. Also, make sure it rolls over at the end of the year; having to spend down each year is goofy -though we still have an incredible first aid kit because of that last year.
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