There are a few employee co-ops, but I don't know how good they are. Over here in the UK we have the Co-op[0], which is a national chain of small local shops. It's a consumer co-operative rather than a workers' cooperative, though. I don't know how well it works, or what its challenges are, but it definitely exists.
Don’t forget John Lewis/Waitrose and the excellent Richer Sounds:
Richer Sounds boss in £3.5m staff giveaway https://www.bbc.com/news/business-48269171
The Co-op (referred to in [0]) is also a bank, funeral directors, insurer, and solicitor! They're really quite successful to be honest.
Nationwide is another example of a successful cooperative as well (large UK bank, particularly in the mortgage space). They're customer and employee owned I believe, my wife and I got £200 last year as a profit share for being customers.
I'm a huge fan of the model, but it's difficult to get going. I think they're also more expensive to run as their operations tend to be a little more complex.