These things are small, the size of a Dyanco ST-70 choke and I first caught wind of the nickel PS choke thing paging through Sound Practices and seeing the ads for April Audio selling the Nature Sound permalloy PS chokes. For those of you not familiar with Sound Practices, Spend the best $29 you ever will and learn about Papa Joe. Back to the topic at hand.... I was firmly in the PS choke is a PS choke camp and laughed at the concept of $500 a pair for PS chokes. I had the great fortune to meet Uchida-san of April audio before he passed away and the most memorable moment from the visit was him cradling a Permalloy PS choke in his hands and passionately stating "Very beautiful sound".
A number of years later, Steve Berger who took over Aprilsound paid me a visit with a pair of the Nature Sound chokes and I skeptically clipped them in place of some potted milspec Low DCR chokes. My life has never been the same. Like my first experience with mercury, I was hooked and needed more nickel in my system.
That was over a decade ago and the stash has been growing ever since. The good news is my habit doesn't take up anywhere near the space that Jeffrey's does.