Call me cheap, but I've been waiting for the rest of the DLC to go on sale like the Armed & Dangerous and Super Sports packs did a few weeks ago. I like this game a lot, and just recently started playing it again with some friends who just bought it. But having purchased the game on release day, and having burned through pretty much everything there is to do in the game, there's not much incentive for me to keep going.
I feel like 560 MSP is a bit much for the content you get for the existing DLC packs, but I jumped when they discounted some of them to half price. I figured it'd only be a matter of time before they'd discount the rest and I'd pick up the Lambo and Porsche packs, too...but so far, no dice.
Oh well...just putting it out there...plenty of other stuff to keep me busy in the meantime.