I got a 50,000 MR targeted offer for a Gold Business Card. They waived the annual fee of $175 a year. I signed up and immediately got the points after the $5,000 spend. Then 2 months later while I was logging into my AMEX online, I saw a pre-approved offer to upgrade it to Platinum. They gave 25,000 miles to upgrade. I already have an AMEX Platinum personal but I went for it since I got another 25k bonus miles plus the $200 airline refund.
The only downside is I would have had the no annual fee for a year but after upgrading it was $450 annual fee for the upgrade.