I can see a use for the Peng in an anti-carrier setup,the aoe is nice.
I think it's still a bit OP against escorts, but i totally ignore them on my cruiser. So I'm not sure how i feel about them.
I think the thing i hate the most about them is that only Feds have them. I REALLY hate that. It's like the Devs gave a big FU to my faction. here you go Feds, have a Klingon torpedo. You Klingons, no.