Not very good. The writing is okay, but walking away isn't better than deluding yourself with justification. Yes I get it's all metaphor, but that doesn't make it better.
If you actually read the thing, within the literal story it never says there's actually anywhere better, or any better place could exist.
Walkaway by Cory Doctorow is a decent spiritual successor to the ideas in Omelas.
It also plays on the comforts of differently structured societies like Le Guin does in The Dispossessed.