For Dragon's Mirror to summon FHD? Just better hope DM don't get sent to the GY by GG. One thing i don't like about numing your own deck is the potential of losing a card you need. And for this option, losing FHD to Enemy Controller or Curse Of The Anubis
Not everybody have a lot of Gems to spend or willing to add money to get 3x DM. Of course there are fair prices but there's reasons people don't add money to the game
I used to run Five-Headed Dragon with Necro Fusion, That Grass looks Greener and Strong Wind Dragon (2400 ATK 6*, takes half of tributed Dragon monster's ATK and has piercing).