www.CostaRicaTicas.com

OK, so I'm gold now, never played it right. I got it by flying the 25k, so I'm saving my Platinum challenge for next year. Anyways, I want to make sure I get the upgrade thing right. Is the key to just book ahead with miles to get into biz class? I booked a flight to LA from NY over MLK weekend, cost me $275 bucks all in, rarely that low. These 500 mile upgrades cost 30 bucks apiece, would cost 150 each way, or $575 for biz class round trip. Just doesn't seem worth it to me (although much cheaper than buying biz class), if I have an exit row. Now If I was going to bundaland, it would be 300 bucks each way, and I don't know if I can do that if I book with the 40k miles.

Is there such thing as a "free upgrade" if there is room? If so, how rare is that?

I'm talking American Airlines.

I've been using miles so I only have ~30K, so judicious use is key until I get platinum. Was supposed to go to Asia biz class for work and now that got scrapped for something else here, that would have been amazing. Oh well.

Any education, greatly appreciated.

I'm gold on American airlines as well if you book with miles then you have to use miles to upgrade, you can not use or buy certificates to upgrade for a ticket you bought with miles. If you book class Y or B then they give you a complimentary upgrade not need to use a certificate.
Continental gives free upgrades with their elite program, none of this certificate hogwash, plus you cant always use those certificates that you buy