Cinematic is a good take on the signature. For movies especially it gives you the sense of being in a well-tuned small theater. Its capabilities for bass really shine here.
Regarding the comfort, it's a mixed bag. I've never found their older models to be high on comfort, especially compared to the PX8, which I thought was amazing for comfort. The pads have have an interesting memory foam kind of material that need a few minutes to warm up and bed into the side of your face. I found I needed to break in my pair for months and months after I bought brand new for me not to notice them on my head as much.
For isolation, they are closed, but not entirely. I would say maybe 90% closed, so on louder volumes, a bit can leak out.