SST -
yup, Delta's coupon issuing method is consistently fastest, in my experience. UA can be just as fast (with less footwork on your part - one simple call), but they can also take a couple months.

Consider Midwest Express: you have to FAX or mail a request in writing. I faxed mine a week ago, and they haven't even deducted the miles yet. Something tells my YX is going to get the record.