We have a Chariot Cougar 2 that we bought from REI. I realize that it's above the price range mentioned here, actually it's in the same range as a Burley. However, I put off getting one for over a year because I was too stubborn to pay for a premium trailer, yet I wasn't really happy with the cheaper ones.
Anyways, I am THRILLED with the purchase for several reasons. It's well-made and feels very solid. It has an adjustable suspension that you dial-in based on the weight of your kid/kids - works great. Also, it has two stroller wheels that attach to the front corners of the trailer if you want to use it in stroller mode - I find this vastly superior to the arm & single wheel of the Burley and others. I have people ask me about the Chariot all the time when when we're using it as a stroller just because of the dual front wheels.
Oh yeah, I've been pulling our two boys in it all summer and it still works like new. We have a 3 1/2 year old who weighs about 39lbs and a 1 1/2 year old who weighs about 35lbs. (yeah, big kids I know) If the Chariot can hold up to the abuse of my two boys, I think it can stand up to anything.
In other news, I'm building leg strength like crazy pulling ~100lbs of boy and trailer behind me.
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