Scenera BARELY fits...what are my other options?

The scenera is for a little boy I watch and he's in the car for 4 miles a day (I take him back to the preschool where his mom works). He is rear-facing (and will be while I have him this year).

We just found out we are expecting #3 in May, and although the scenera is ok, it's not my first choice for a newborn and not my first choice for an "all the time" seat. We travel a LOT and I want a comfy seat for this little squishy.

Right now, my almost 6 YO (42 pounds 47 inches) is FF center in a Radian XT and my 3 YO (28 pounds 36 inches) is FF in a Marathon outboard (she gets car sick, so we turned her at 2 1/2).

I CAN get the Marathon center, but it takes up more room than having the XT center.

I'm debating whether or not to skip the infant seat altogether, but I have tiny babies (5.5 pounds and 7 pounds).

Due to the stupidity of the designers of the back seat of my car, it's not very car-seat friendly. (subaru forester). I almost cried when I got the scenera in there because I knew that it would work if nothing else would.

So, I need suggestions. I'm debating the keyfit, but there is no where for me to try it. I just found a local baby shop that carries combi items and they have the shuttle and the coccoro. Of course, I've got Wal-Mart and the snugride and the Evenflo discovery options.

Anything I'm missing? Oh! Another thought I had was to move DS to a booster, put DD in the Radian and see if the Marathon would work, but as I said, I have tiny babies, and I'm not sure it would be the best idea. My Marathon expires May 2012.

and due to the recline of the radian, I can not rear face it in my car.

I think your Radian/Marathon combination is going to help you since that combo takes up much less space than most others. I'd keep it as long as it works and the kids will fit.

I do know that my Combi Connection worked well with a FFing RN, but I have no idea about how a Keyfit would work. Maybe someone here can try it for you. I Coco would probably work too, but I'd imagine that you should be able to find an infant seat that works if that is what you want. FWIW, the Coco fit my 6#er as well or better than the infant seats I tried.