Here's a clear video of the new BMW M4 starting up and revving its twin-turbo straight six. And here's an onlooker saying it sounds like his Prius.

Now, I like all kinds of engine notes, from thrummy threes to barking tens and soothing sixteens. This M4's engine certainly gets close to a traditional raspy six sound, but sorta also sounds like a faraway leafblower.

And I can't help but think this M4 sounds a little quiet. For some, that's not a bad thing, and for others it's a major disappointment.

What do you think?

(Hat tip to Austin!)