Combination carseat/booster?

[MSMOM]

OK, I'm going in circles and I need help! The situation is that I need 2 extra carseats for our sitter's car for picking up preschool etc. The seats won't get alot of use so I don't want to spend a ton but of course safety is the priority and it would be nice if I could have some longevity out of them. My DDs are 2.5 and 1, both are very tall so far, my oldest very skinny, my youngest more average weight. I was thinking about the CarGo, Evenflo Generations or the Recaro (but expensive) as they could eventually work as boosters. We have them both in Britax MA in the main car. Am I thinking too far ahead on the combination booster idea? Any other suggestions for 2 tall girls, minimal usage now but maybe more usage later as a booster? Many thanks!

[Joolsplus2]

Nope, sounds great. The thing about combination boosters is that they have tall top slots, so you get the most bang for your buck (almost as tall as the marathon :) ). I wouldn't want a 1 yo FF at this point at all, so the Cosco Scenera is a nice cheap choice that can rearface another year or 2, then go FF till age 3 or 4, depending on how fast she grows...not bad for $35-$40 :) (www.albeebaby.com has the Cosco Apex for $89, it's a good combo seat, but requires a headrest or very tall seatbacks in the car, to provide good head support for a taller child).

:)
Julie CPS Tech and mom to 3 in seats
http://www.cpsafety.com/articles/RFAlbum/SarahMA.aspx