Well, originally we planned to just get a Marathon, Roundabout or Wizard and use it from newborn on, but someone here (sorry, don't remember who- it was awhile back) went on at some length about how newborns just aren't so safe in convertible seats. SO... we went ahead and got a Britax Companion (for only $150, I have to brag) AND a Wizard (for about $240) We have more $$ right now (well actually a few months ago) than we will when we need the Wizard, so I wanted to go ahead and have it on hand. It came down to the fact that we weren't buying most big ticket baby items and we just couldn't bring ourselves to choose a carseat based on price alone. I really like the Companion- it has some safety features that no other infant seat does and we decided on the Wizard for two reasons- 1. the side impact protection and 2. the knob to adjust the straps (without re-threading them)
So- there you have it
We were a little concerned about fitting the Wizard in our Honda Civic rear-facing, so we tried it out at the store- no problem at all. Fits great and goes in easy and super secure.
-Angela
So- there you have it

-Angela