Im not sold on magnets being able to clamp the razor as securely as threads.
Noted.
The subject of the suitability of neodymium magnets, whose magnetic energy value is about 18 times greater than "ordinary" ferrite magnets by volume and 12 times by mass (quoted from Wikipedia), has been extensively debated around here before and the verdict was near unanimous.
I have full confidence in the Amakuni’s neodymium magnets, which is further helped by a life-long warranty.
They may not hold as securely as threads, but for what they are supposed to do I very much doubt they need to.
B.