A.M.
i believe the only one on the market in the US with protection for side impact crashes is the Britax Blvd. It is a great car seat and can be used up to 65lbs. It was at the top of the consumer reports ratings. The britax marathon is also good but doesn't have the side impact protection ie the wings. The only downside to the Blvd is that it is big. The Blvd is also expensive but then the cargo is priceless. I have mine permanently installed in my car and when we travel, I bring the roundabout as it is lighter.