If it were my house I'd use a glossy interior oil paint from as high a quality brand as you're comfortable paying for (though convenience is important in buying paint, too). High-gloss latex would be my second choice.

I would use Aura or Grahams 100 percent acrylic satin or semi gloss. Oil based paints may be more durable, but the difference in durability these days is minimal if you are using high quality paints. Of course mid grade or low quality latex paints are a bad choice for high moisture areas. Personally I would just never use an oil based paint in a shower area because moisture + oil based coating usually equals mildew growth.

Thank you both for your responses.