Guardian Cards

[Kingdom Xathers]

How popular are "Guardian" Monster Cards nowadays (you know, the ones that cannot be summoned without a specific Equip Spell Card on the field)? I'd like to know because I just received a request to create one, and I may as well prepare myself for comments if I decide to post the finished card in the Realistic Cards Section.

[Doom™]

I don't know how popular, but I think they aren't. They are kinda hard to summon in my opinion.