I don't own either of those machines, but having been on here a while now, the 460 (Hegner clone) has had some very satisfied users posting here in the past. Some have said, more or less "just as good as the real Hegner).
The 406 LOOKS just like the Excalibur Ex 18 inch version. I have an Excalibur 21 inch version myself and am delighted with it (it's over 5 years old now, and never a problem), BUT there have been several reports on here from people who have bought this Axi "re-badged" version of the Excalibur machine range (18 inch, 21 inch, and 30 inch). All had several serious problems with them - to the extent of having them changed by Axi under Warranty in some cases and one has written "never again".
It seems that these Axi versions of the Excalibur machines have been somehow "cheapened" internally with it seems, not very good results.
To get the full story you should search through posts in this section, firstly for a post by member Droogs who has the full story (it's complicated) and also for posts by several others (none of whose names I remember, sorry!) all of whom have had problems with these Axi versions of the Excalibur range.
If you want to know the full "story" of the "real" Excalibur (General International Co) machines, not the Axi versions, let me know and I'll dig up several posts I made here on that subject from when I was researching prior to my own Excalibur purchase 5+ years ago.
HTH and good luck