We own 2 of the Marathons and 2 of the Regents! We moved our 4 year old into the Regent when baby came. The Regent is a little better for the bigger kids but you certainly don't have to change. We just chose to move her.

**Note Use a pad under the base. The base is smaller and tears up your leather seats!

From the moment you pick it up you know why it demands the price tag. It is heavy(not too heavy though) and you can feel the quality. We researched every seat out there and this is the one we decided was the safest.

It is easy to install although I found that the directions were lacking and hard to follow so I went on the internet to get help doing it properly. Britax did a good job informing us of a recall and sent us the replacement part before I had even heard about it. I was impressed!

Versa-Tether is patented by Britax, for the most security in both forward and rear facing. Makes it worth the $$ Tethering in the rear-facing mode provides additional stability and reduces movement because the weight is stabilized between two points.

Easy Recline Adjustment Handle provides a range of comfortable seating and reclining positions. LOVE this feature!

I know that the price tag is high but it is the only one that we found that had the 5 point harness that they can stay in here are the stats!

Marathon is approved for Aircraft Use.

Rear Facing :
Age: Infant to toddler
Weight: 5 to 33 pounds

Forward Facing:
Age: At least one year old
Weight: 20 to 65 pounds

Do your reasearch and Please keep you little ones in a 5 point harness for as long as possible!