I have both, a '20 Comp and a '20 MYP. It's funny, people think they're essentially the same car, (similar size and performance), but you're right in that they're very different.
The Y is more cushy and MUCH larger inside, with tons of legroom in front and back as well as a larger trunk floor area. It's great for moving the family around in spaciousness, but good god is it noisy. I won't take lengthy trips in it on the highway. My Comp, with all of its roaring and burbles and glorious sounds, doesn't induce a headache like the Y. My M3P wasn't nearly as loud, and my MXP was a vault (and a lemon).
The Comp is far more fun and garners a lot more attention - they're beautiful cars inside and out - and even though my Y was $61k, my Comp was cut from $84k down to $68 and change. It just feels like a ton more bang for the buck.
The M3P was fantastic, though. I miss the feel of that car every time I get in the Y as they are very, very different, but its low entry and exit and "the dog doesnt go there" trunk forced the change.
I've actually found that nearly no one cross shops these two cars - you're probably the 3rd or 4th I've ever heard mention them as comparisons - and the others only mentioned them when they see ours parked next to each other. That speaks volumes about the brands themselves, let alone these two specific models.
I love EVs, but they're the angel on the left shoulder. The Comp...right shoulder.
