I've watched the first 3 of this series so far (8 episodes total). I really like it. Some of those sleepers are great, and let's not shit on the super cars either.
I would absolutely drive that little '71 Ford Pinto. It was pretty cool.
I liked the all black Thunderbird also. It looked really good after they completed it.
Also, the Honda Odyssey is a really good idea for a sleeper. A mini-van that's fast.
But really, who wouldn't love to own either the Viper or the Ford GT? Those cars are gorgeous. More so than the Lamborghini, in my opinion.