[aerohead]

Someone I dated in college had the Chevy version with four-banger and manual. I drove roundtrips in it, from Lubbock to Houston. It never demonstrated remarkable mpg.
The V-6 and V-8 are less efficient engines, heavier, are 'shoe-horned' into the engine bay, and require drilling holes in the inner fender-wells to reach some of the spark plugs, and loosening one motor mount and raising that side of the engine to reach the last plug!
I think you'd end up hating the V-engines.
The fastback body IS attractive, but it needs the rear spoiler. The roofline is 'wrong.'