Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Maybe mine is defective?

Am I the only one who has a problem with the Britax Marathon? The straps on my Marathon do not tighten evenly. The harness is always tighter over one shoulder than the other. I called the company to ask about this, and they said there was probably a twist in the strap somewhere behind the seat. I was told to take the harness apart and put it back together. I did this, but the problem has continued. As far as I can see, the problem is not the result of "user error." I tighten/loosen the harness exactly as the Britax customer service person told me to. So I hate this car seat. It seems very unsafe to me to have one side of the harness always too loose. Britax will not replace the seat, despite the fact that it was "recalled" for a harness-safety issue. I'd never buy another Britax.