What deck(s) is Guardian Eatos good for?

Guardian Eatos
If you have no monsters in your Graveyard, you can Special Summon this card from your hand. You can send 1 Equip Spell Card equipped to this card to the Graveyard to select and remove from play up to 3 monsters in your opponent's Graveyard. This card gains 500 ATK for each monster removed by this effect, until the End Phase.

Any other? Please discuss.

Eh...really not a whole lot besides Decks based more on Equips as its effect indicates and revolves around. Guardians and Deformers/"Morphtronics"/Power Tool Dragon being the only Decks that cater to Equips more than others and it's not like one would WANT to toss in a couple Equips just to use her either.

While you COULD possibly try it out as a quick big beater with its Special Summoning effect, unless you draw it in your opening hand or perhaps on your 2nd turn, chances of that are pretty slim as well. Or if you use a Deck based around Dimensional Fissure or other removal effects like Banisher of the Light/Radiance and Macro Cosmos, Soul Release, Bazoo, Skull Lair, etc.

its possible to make a macro otk with it

That's why I brought up removal...problem is is that it's not exactly reliable or consistent either...at least for higher level tournaments.

Nope. Too slow, can only fit in a dedicated equip card deck (Warrior toolbox with the likes or Freed or Gearfried?). Plus a dedicatred equip card deck is HIGHLY unlikely to main Macro or DFissure, so this card isn't for DDReturn decks either. Its a misfit really. I wouldn't know where to put it and make it good enough to main or even side...

Well, as said, Equip Decks only have Guardians and Deformers that really use them at all. Deformers actually aren't THAT bad once you get a good feel for them. Not supreme or anything, but they're are definitely worse things than them.