I live in Washington, D.C. and have the Nomad and the Travoy. Love my Travoy -- makes a lot of sense for the city -- but have ended up primarily using it as a "hand truck" -- walking to a new supermarket three blocks away. I also use the Travoy for lugging camera equipment (again, as a hand truck rather than hooked to a bike). The Travoy's bag options (grocery, luggage, etc.) are absurdly expensive (and I have them all) so factor that into your decision.
The Nomad is a great trailer but for me, in the city, the Travoy works better.
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