I was just about to chime in with nearly the identical thing posted by Paolo.  I think many poser users(since this may be their first exposure to luxrender) will be hard-pressed to get themselves out of the firefly render time mind-set.  There really is no comparison between firefly and luxrender and I've used both fairly extensively.  Not even an apples/oranges comparison.. more like an apples/onions comparison.

 

This is just my own two cents.. but it's like comparing a graphic novel artist and a portrait artist.  Both can be just as equally talented; yet the results are vastly different.  Someone like Olivia de Berardinis can crank out an absolutely stunning airbrush painting in a few hours; where some of the renaissance era artists spent weeks or months producing masterpieces.

 

To use Luxrender and to be a speed-demon is counterproductive.  Unless you're producing tiny resolution-ed renders meant for something other than to push reality, poser and luxrender to it's(and your) limits artistically.  Some things in life and art take time to acquire and luxrender is one of those things that just takes time.  If you want blazing-fast renders, try SLG.  Using SLG, I can carbonflux a render in a just a couple hours and achieve realism that (and yes I'm saying it)firefly would have a seizure trying to replicate.  It sounds offensive to me in my head as I'm sitting here typing it and I'm not purposely trying to be so; but, the expectation of 45-minute 3000 pixel masterpieces are a product of the microwave oven mind-set.  If you want to make a test render to check lights and materials.. keep everything at your full final resolution and just turn it down to 25% in reality and lux will give you a few hundred passes in 15 minutes or so; this method can give you an incredibly accurate test render.  If all is well, cancel it, turn the res back to 100% in reality and let 'er rip.

The other thing where lux(and others) are head and shoulders above firely is in the ability to suspend and resume a render.  How about going to bed and forgetting that it's mandatory update night for windows/microsoft and having your computer reboot in the middle of an overnight render?  With firefly, you're toast.  With Luxrender it's simply a matter of resuming.  Sooner or later the devs at Lux will get the gpu rendering issues resolved and the speeds we all render can take a big jump.

I spent six years of my life struggling with Poser.  Never an issue with composition for me since I tend to stick to the pinup/glamour style renders; but with materials and lighting.  I can't think of how many hours I spent fighting with poser lights to get the effects that I wanted.  Yet, thanks to some tutelage from Paolo (how many other artists with a listing on IMDB have time for us little guys?) reading a few glamour photography lighting tutorials and a bit of play; my lighting issues were over.  Don't even get me started with poser's material room.  With Reality, THAT little problem is over too.  I have used it enough with DazStudio that I know what to do to get what I want.

Frankly, I'm eagerly awaiting more.  I have a few poser artists on my favorites list that I'd really like to see using Reality and pushing luxrender to its limits(Fallen, MGTCS, eekdog, and barryjeffer all come to mind.. hint hint nudge nudge).  It's just that I see folks dissing Lux because of the enormous render times and I want to shake them all and yell at them because in the same hands; the end results of each render engine are beyond comparison.