The HI kit worked well in a DC headset, but I couldn't stay with it. My ears are too big & stick out too much, so there wasn't enough room in the domes for them, & the pressure caused pain very soon. I can't use any production headset, I have to make my own. However, I don't recall having that trouble with the SPH5 oh those many years ago, I think there is more room inside the domes. Every ANR I've tried has the same problem.
The upside of the HI kit is that it's reasonably priced, & having to give it up didn't kill me financially. I am using the speakers from the kit, & the mikes can be reused for something, maybe.
Again, the noise cancelling worked well, flying in a 412 at the time.