I saw a used Impala on the lot at the local Nissan dealership a few months ago, and was a bit tempted for a moment. It was a 2018 2LT or something like that, with about 35,000 miles, and I think they were asking $17K. Didn't seem like a bad starting point. I didn't look under the hood to see what engine it had. It was listed as having the 3.6 V6, but they also listed the EPA rating of something like 22/30, which I think was the 2.5 rating. I'm thinking the 3.6 is 19/28?
Anyway, the car crossed my mind a couple times, and there was a few times when I'd have a good day on the market I'd even think hey, I could cash out some and go buy that Impala! But, in the back of my mind, I was just getting a bad vibe about it, so I passed. And eventually, it wasn't showing in their online inventory any more, and I figured, no great loss.
I did drive one at a test drive event a few years back, a well-equipped model with leather, sunroof, and an MSRP of around $40K or so. I never thought the day would come that an Impala would sticker for that, but the Impala has definitely moved upscale with the later generation. I used to have a 2000 Buick Park Ave Ultra, and I'd say the Impala would have made a worthy alternative to that.