Vue 5/6 and Carrara have poser import as far as I know, but they have different material and lighting settings, dynamic hair works in  both programs for example. but you do have to do a lot of work to get the same results. I know the render possibilities of Vue are far more extended than poser, but you still have to set up your posing in Poser. You can still change your posing after you've imported it in Vue or Carrara, but you'll have to go back to Poser. (they keep a link to the program) For Vue there's even a special program that's add reality to poser figures similiar to those of the realitieshaders , we have here in the market (I don't advertise so I don't call names) I like the possibilties Poser offer and I don't like extensive switching between programs. So I'm afraid I'm stuck to it. I think for outdoor scenes Vue and Carrara are unbeatable compaired to poser, but for interior scenes (which I do a lot) I like to use poser because it seems more suitable.
DAZ-studio also handles Poser-contents but it lacks some mayor abilities like a Poser import and export function, but that discussion is overdue.

-How can you improve things when you don't make mistakes?