Carseat question
We used a Graco Snugride with Matani until he outgrew it at a mere 4 1/2 months, at which point we moved him to his Britax Roundabout, which he still uses. We were very happy with the Graco, and love the Roundabout.
Now, assuming #2 is on a schedule something like Matani, s/he could be ready for the Roundabout in about 9 or 10 months (i.e. at around 4-5 months old), at which point Matani will be about 30-ish months. Although he was a gigantor baby, he is now pretty average in height and weight.
Since I am heading to the US soon, I thought I might pick up Matani's future next carseat while I'm there. So, my question is, what would you recommend for an average-ish sized 30-ish month old kiddo?
I was thinking about another Britax -- maybe Marathon or Wizard-equivalent, but I wonder how long Matani should be able to use one for...? Could a "youth" seat like the Regent be more appropriate by then? I'd like to err on the side of whatever Matani will be able to use for longest, whatever is safest, and whatever takes up the least amount of backseat space.
-- Wait, OK, I just did some research before I posted this. It looks like (1) Most kids will not outgrow a Marathon until college, and (2) the Regent is ginormous. Is that right? So... I guess I'm wondering if I would even need a Marathon instead of another Roundabout? How much bigger is the Marathon? Would a backseat be much more crowded with a Marathon and Roundabout than with two Roundabouts? (We have a Ford Focus, right now. Something tells me that we are going to want a bigger car about, oh, say, 9-10 months from now. No?)
Any advice / guidance would be much appreciated.