I don't have any experience with any of the 900's but totally love my 740 turbo wagon. I've had/have 240's and 140's and like the 740 much better. It took a little while to get used to styling but you should be comfortable with that considering your other Volvo. Handling issues of RWD shouldn't cause too much problems. Now that my girlfriend has gotten her hands on my wagon she has become a RWD convert. I admit that having toy IPD has in their catalog for suspension might have made a little difference in her opinion ;) Unless she is leaning on snow and ice the transition should not be too shocking unless she really pushes hard in the corners.