I have been using Girabaldi hair since it was first released. Girabalidi works well with 3Delight. My avatar here is a render done with Girabaldi hair.

Girabaldi and LAMH both generate hair as 3Delight curves. Iray apparently has some curves but not equivalent and apparently not useful for hair. Both can generate an Obj file that can be used in Iray or Luxrender, but you have to reduce the number of stands generated.  You cannot do 100,000 curves, which is what I normally do with 3Delght.  The other issue is the shader. Girabaldi has a special 3Delight hair shader and a lot of the appearance comes from that hair shader. When you use an Obj to render with Iray or Luxrender, you are on your own as far as shader. I have never seen a Luxrender or Iray render of Girabaldi hair that looks as good as the 3Delight renders.