FYI: I upgraded from the free Hilton Amex (which I'd had for years) to the Ascend early this year (once a big upgrade bonus offer showed online), and then roughly half a year later I got an online offer to upgrade form Ascend to Aspire for another 150k bonus points! So I'm getting the double the bonus points, while having "just Gold" for only about half a year, than if i"d upgraded to Aspire directly (which wasn't available at that time with a bonus).

And the great thing about these upgrade offers (both from Chase and from Amex) is that they require no credit check, do no credit pull, and don't appear as new accounts on your credit report (in case you're trying to stay or get below Chase 5/24). I hope even more cards from banks think up upgrade offers with bonus points/miles in the future! (Amex was the first with Hilton->Surpass for years and year, while this is the very first time I'm aware of Chase giving an upgrade bonus.)