I'm in a similar boat with Plat75, and I will likely need 10 additional nights. There are several Cat. 2 properties nearby so I could book 10 award nights and it would cost me roughly $750 worth of points. I looked at my spending this year and the extra point per dollar would get me roughly half of that value back, but I can't decide if the your24 would be worth the rest.

In your case I wouldn't go for it for $1200 based on everything i've read and my brother's experience with his ambassador so far.