The way I figure too is the so called "high" interest that I would get on a few hundred dollars ought to work out to about 5 bucks in the long run. Not enough for me. This way I can buy bits at a time so it doesn't hurt quite as much as all at one time.
Luanne, did you see my question to you? Are you saying the main reason to direct it to your onboard instead of taking the certificates is so that you don't have to remember to bring them with you? I've just been collecting the certificates that they mail me. Thanks.