These are two different animals. The Sundance is a laminated sidewall unit while the Trail Runner is a metal sided unit. Both have aluminum sidewalls, but the Sundance wall is going to be both thicker and more energy efficient. The interior of the Sundance is also going to be an upgrade from what you would find in a Trail Runner. The Sundance features rasied panel all hardwood cabinet doors, while the Trail Runner has a hardwood frame, around a panel insert for its doors.
Is the Trail Runner a good trailer? Absolutely. It's just that the Sundance is the "next" level up in both amenities and price.
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