Given that I'd like to haul more than just the dog, I'm thinking that the Burley Flatbed will be a good option. It rides flat, the bed area is large enough for the crate we'll be getting (plus there are tie-down points) and I can use it to haul groceries and other such assorted junk when I'm not carting the puppy out to play at the park.
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"I feel like my world was classier before I found cyclocross."
- Mandi M.