Yup, these are bass cannons. I'd say at the 370 USD price point, they're a competitive option if you're looking for maximum bass headphones and you don't mind the hilarious ergonomics. The bass extends deep, it hits hard, and there's a lot of it. I recently heard a Fostex TH-900mk2 Sapphire Blue with ZMF pads, and I think the R9 does bass better. The Fostex had a lot of bass, but it lacked impact and sounded "slow" or "soft", like being whacked by a plush pillow.

I generally agree with your treble assessment, though I wouldn't call it "V-shaped" given that it doesn't have the treble elevation that I would consider to be V-shaped. It has enough treble to avoid being dark sounding though, so it's generally done well. The bass is very prominent, and everything else is fine. This combo allows the bass to take center stage, without making the bass muddy. It's also extremely comfortable.