I've played enough with Aftershock and Masamune and now I went back to my Dominus: You can tell me all you want, but I know that there is a huge difference with these cars. I'll miss the extra dribbling with the Masamune. Dominus 4 Life. I'm instantly playing better with it.
I've bought all 6 DLC cars on Xbox so far and I'll probably never use them.