I don't think that choosing something so hard to learn and to masterize like a 3D software should be only a matter of bucks ;) Carrara5 is cuurently under beta testing, but beta-tester are under a N.D.A. probably so they can't talk. I would say that if Carrara suits currently your main needs, then wait for the offical new version information ! Otherwise the public price of Lightwave has almost been divided by 2 by Newtek to be decreased down to 795USD (http://www.newtek.com/news/releases/08-01-05d.html), so it will be always time to made up your mind and to switch to LW if you want. Just my 2 cents :)