I've recently been playing with both of these renderers and IRAY.  I am really Loving Carrara Luxrender and also am finding DAZ Reality really good, both have pluses and minues.  Carrara Luxrender seems to have a lot of noise I haven't yet solved how to correct. Reality generally less. I am posing a couple comparision pics, I am finding the Carrara Luxrender to look more photoreal to me (I know I have more to do to get there). But Reality is a bit easier to set some aspects of my scene.

 Overall, nothing is more user friendly and Carrara for set ups on their regular renderer. I definitely have to use texture maps verses using Carrara's texture room to create textures or make certain modifications.

 Question for you, has anyone any good tips on 1) reducing noise for Carrara Luxrender  2) Better ways to tweak textures in Carrara Luxrender?

Any other thoughts is very welcome. 

 Top from Reality Bottom pic Carrara Lux