So glad to see so many RD heads out there. I also started out with RD4.
 As such, Carrara's traits(rooms and what not) feel natural to me. But when I first got Carrara, I would always model in RD4 and import. As I (barely) recall RD4 had different modelers other than spline. Perhaps Carrara won't totally run with the High-end apps, but whenever I look at a Maya manual, I just about go skitzo.

Nobody's ever going to mistake my work for something from Lucas Arts. But I'm in this for FUN and only FUN. Carrara delivers that in spades and the only limitations I've found in it are mostly my own. I just wish they'd hurry up with the boxed version. I hate not having a book.