tamahangane vs iwasaki


I've did some reading on the fourm reading tamahangane as the best of Japanese razors.
But found one on ebay used.
Questions)
1) Between the 2 what would be prefered. Personal or as razor companies.
2) to horn these myself what type of stones would I need. The store guy stuggested 12000. Just put water and slide away.
3) horn is done just as Euro razors.
4) time limit or no. of strokes.
5) 50mm length vs 60mm length.

Iwasaki is cheaper and is new. While Tamahagane is used and well price is well over 500. I've extended the guy an offer on ebay but now have heard back.
Advice opinions all welcome.
~Raijin.