I personally like the looks of the '71 ebody's best, Challenger and 'Cuda. And if you're a collector or restorer and want a big block or high optioned car, '70-'71 is pretty much the only way to go. But if you actually want to
drive your car, a '72-'74 is the best deal. They usually cost less, and swapping out a 318/auto for a 340/4 speed or 440 raises the value, regardless of the matching numbers thing.
I bought my '72 because it was the first e-body I found. In retrospect, I probably should have waited and looked for something a little cleaner. But, since it was already a non-numbers matching car, I don't have to worry about what I do to it. Which is great, because the 340 4 speed I'm dropping in it will only raise the value. And I don't have to worry about messing up some numbers matching, 1 of whatever car by driving it every single day. Which is pretty much what I do with my '72, it's my "newest" car and my daily.
And when I finally take it off the road and rebuild it, its getting '71 fenders, grille and rear markers. Tail lights are staying, I like the '72-'74 tails better, and it lets the collectors know its not actually a '71. And since its a '72 I don't have to move the bumpers.
Just makes it easier, there's no dilemma about keeping it stock. In stock trim it was a base model grocery getter with freeway gears. With a 340/4 speed, 11 3/4" disks and 11" drums, B-body rear, 275 wide tires and hotchkis gear, its a street bruiser. And I didn't lose any money because its not numbers matching or bone stock anymore.
Regardless of year, the value of these cars is going to go up. The '70-'71 cars will always be worth more, and the collectors will always be willing to pay more for one. But if you're not worried about having some numbers matching show car, the '72-'74 cars are the best deal running.