Infant car seats with two toddlers

I have a big fullsize truck and there is room for my newest edition in the middle backseat between my toddlers, what car seat do you ladies recommend that isn't huge and bulky and will fit comfy in the middle? Price is not a HUGE factor, but durability, easy of use and I'd prefer something not completely heavy.

I believe the Chicco Keyfit has the slimest base width and I always hear awesome things about. Next would be Maxi Cosi Mico, which we have and love.

There are some slim convertible ones too that you can just put in and leave. Eddie Bauer makes some pretty slim seats. We had a Chicco Keyfit 22, it was pretty slim and easy to install the base.

I don't know of many infant carriers that are really slim however I know the Diono's and Combi Coccoro are really slim and both are convertible seats.

I just bought the chicco keyfit, I hadn't used it yet but I did buckle it in to our tiny eclipse and it fits very well in this itty bitty car, I can't imagine it not fitting in a truck even with 2 car seats. My brother in law has a truck with back seats and even with my son and nephews car seats there would still be plenty room for this infant .

Thanks ladies!