Urban Artifacts was awesome! My only regret was not having enough time to properly browse, but I did give it a quick run-through, and there was so much cool stuff in there!
When Toys Were Toys used to be in a strip mall, but the new location is pretty cool, not as visible from the road though. They're about a block down from the Wheels O' Time museum (which also looks amazing, but we never get there when it's open).
Romney Toy Shop was absolutely my favorite stop, it reminded me of so many places I loved to shop at in my teenage years when I lived in Omaha, NE. (The Brass Armadillo, Meadowlark, and Blue Ribbon Antique Malls, Radial Street Flea Market, and Krypton Comics and Toys, for any Cornhuskers out there) They have so much in that little shop, covering a wide range of eras and interests!
My son has been a total car nut since birth, so we took him to the Wheels of Time museum a few years ago. I had honestly expected to be a bit bored by it, but we actually all really enjoyed it. It's a very neat place!
But yes, the Romney Toy Shop is my favorite type of used toy store. The kind that are jam packed with a million different items covering every possible interest, so full that you can go back a hundred times and never see all of it.