Alpaca, along with being oh so cute, produces a smooth, silky fibre that has a lovely luster. It's a strong and durable fibre but it has no elasticity, the way wool does. It doesn't bounce back into shape. This makes it great for scarves and shawls but not so great for sweaters.
Alpaca plays well with other fibres and is great for blending, particularly with wool as you gain the qualities of both fibre types. It takes dye well but, if the fibre has colour, it will be the base of your dye.
This is a great fibre to work with. You'll love it.