Why the Sisters of Battle?

The Sisters of Battle are one of Games Workshop's worst selling army, a force of human women fighting genetically altered humans, Orks, Tau, Necrons, Chaos, and Tyranids. For such an unforgiving, and frankly butch, universe, it might seem strange for a straight, married 30-something dude to want to have an all-female army. Because of this seeming disconnect, I am going to explore the appeal of the Sisters, as I see it.

The Models
It might seem obvious, but the models are simply some of the best that GW has ever made. They are simple, elegant, and, best of all, metal. Metal minis are an increasingly rare treat. The weight, the heft in my hand, makes me savor each metal mini I own. The feel of unfinished metal minis is unattainable with plastics. I wish there was a better way to express this, but I cannot find it. The best way to see what I mean is to hold a metal mini in your hand and then a plastic. Plastic has it's place, in the making of tanks and Space Marines and the such, but a metal mini feels special and has a magic to it that no amount of bitz on a sprue can equal for me.
Aside from being metal, it's the design of the thing. From the nun-cum-armour suits they wear, to the tasteful use of fleur-de-lis, the Sisters are well designed. The tanks are also cool, using gothic imagery to be less wargame-lite than the Imperial Guard.