V6 stang is faster than your average civic. V8 is better, but V6 is still potent. Gas isn't that big of a deal.
Thing about Civic and other Hondas, and Toyotas, and Mazdas, and other Japanese cars, is that they are:
A) Not durable
B) Cost a lot of money to fix
C) Does not last long
D) Not powerful
E) They are front wheel drive cars
F) They are not fun because there is no torque
G) They are not powerful because there is no horsepower
H) They are slow
For a Civic to go as fast as mustang it needs to be modified and it needs to hook. It simply is not possible on the street tires. Thus your Civic experience will be very borring, since it does not have a lot of torque. Just think your average family car. Some grossery hauling mini vans are faster than a Civic.
For your budget:
Mustang GT, 91 to 93
Mustang LX 5.0, 91 to 93
Mustang GT, 94 to 99
Taurus SHO
Focus SVT
Coutour SVT
Mustang SVO (best car ever made, 400 horse, 2000 lbs, a 4 cyclinder rocket ship)
The 91 to 93 stang is a way to go, since they are light and have small block ford. Later models have a mod motor. Mustangs are modern muscle cars, if you want a small car go with Coutour and Focus SVT and Mustang SVO, for mid size, go with Taurus SHO.
What's good is that all those cars are Ford. So you know you're buying quality, durability, and longevity. This would be a good investment, unlike a Civic, in 5 years you could resell your car for more money. With Civic, in 5 years you will be paying junk yard to take it.