I use both C6 and Lightwave.  I hardly use LW.  the interface in C6 Pro is soooo much easier to deal with, and I have yet to run into something that I HAD to use LW for.  My only gripe with Carrara is it's hit or miss stability problems.  Right now I have it sitting in another window and it looks like it locked up AGAIN...  It needs to be a LOT more stable before Daz is going to be able to successfully market it to professional users and companies.  I am just doing a simple scene.  Mostly done in C6, with 2 Poser characters.  Not a lot of fancy objects all over the place either.  Oh well.  At least I saved it just before it locked up...  I hope 7 is more stable, or I will be staying with 6.2.1 until it is.