I think the Ford Focus RS has the Challenger GT beat. It's 2.3L, turbocharged engine cranks out 350 hp, it also has torque vectored awd and a limited slip differential and weighs about 400# less than the Challenger. It has multiple chassis settings which makes it's more versatile for cruising, hammering the back roads, or hitting the track. It also has launch control and drift mode, making it more fun to drive too.
The RS also has significantly superior handling than the Challenger GT and being a hatchback is a bit more practical. The RS does cost around 2 to 3 grand more. Then again, so does the 2017 Camaro LS and the Mustang GT both 6 cylinder variants have more power and better handling than the Challenger GT does.
In terms of value and performance at the $35,000 to $40,000 price range I don't think there's a better value for a sports car for the average person than the three major sport hatchbacks. The VW Golf R, The Ford Focus RS and the Honda Civic type R.