You're experiencing buyer's remorse. It's usually not the car, but the size of the check that causes it. In your case, you had another thread in here, and got a number of opinions. You heard them all and bought the car. You were really happy when you got it home, as you have another thread on that.
I won't vote in any direction because I don't know you. If you're that guy who lets things like a scratch on the paint haunt him at night, take it back. If you're more concerned with mechanical and structural integrity and believe you have those, keep it.
Either way, don't lose sleep over it. If you return it, another will come along later. If you keep it, be happy you don't have to sweat a ding or a scratch – you're past that – and revel in the idea that you're free to mod/race/drift/drive however you want (playing with house money, condition-wise, so no worries).
Choice is yours. We can't make it for you.
