I dont ride my CAAD9 as much as I should as I much prefer fixed gear riding, if I could find a new Cannondale track frameset, I'd be all over it, they could charge silly prices and I would still pay it
The things that set them apart from other manufacturers may be subtle but they certainly are a step ahead of what other brands are doing, at least with alu frames anyway. Things such as the shaped top tube which narrows in the knee region to avoid knee clash, but then re-widens to provide stiffness, fat tubes, fat rear stays for stiffness etc. They are super nice frames on paper.
Only riding other frames can tell you if they feel right for you in practice though.