I am a worker-member of a (financially) successful worker co-operative in the UK. Basically, the analysis that @CommunistWolf provides is fair and accurate:

• we are very niche, operating in a niche area of technology with high-paying public sector, charityh sector, and international body clients e.g. the UN, various transparency movements etc.
• We compete with the mega consultancies e.g. Deloitte who charge more, do poor quality work, pay their “junior/low-grade” workers poorly but also have a highly paid chief-consultant tier who are paid many times the workers in our co-op
• We have kept wages “low” for our service, in order to sustain the co-operative longer term and we distribute surplus value at the end of the financial year via a payroll “bonus”, subject to our rules that we don’t distribute more than something like 50% of the profits in order to keep an emergency fund for if we’re not profitable for a while, buy some better staff benefits etc.
• While our wages are substantially lower than those of our corp-sector contempraries, for our service, we’re also more highly paid than a lot of workers. Our current salaries are about £43k and we’ve voted to aim to raise these above inflation towards the £60k mark as part of our next plan to compensate staff fairly and keep them in the co-operative. My romantic partner works just the same hours I do, for a megacorp in the financial sector, with far fewer staff benefits, and is paid a value just over half of my salary.
• our “social wage” in the co-op is strong working conditions for the most part, although there are some contradictions which are playing out which limit the effectiveness of these. These contradictions are really derived from the fact that we compete on the market, so any worker benefits or flexibility we gain for our staff must be confronted with the material reality we need to bill X amount to clients and meet our running costs. We do have some strong policies which have emerged from our workers such as menstrual leave for women workers, unlimited sick days and bereavement leave (balanced against a long-term sickness policy), flexible working patterns etc.

In short: I believe co-operatives are a weapon in class war, especially in areas where highly-educated workers can coalesce into pooling group resources, but they are nothing more than a tool and they have their limits and problems. It’s the same as being in a Trade Union; definiteyly don’t discount it and use this as a vehicle for working class politics, but the working class ultimately need a vanguard party drawing together workers from co-operatives, unions, protest movements, etc into a coherent political and revolutionary force.

One reality I have faced is that worker co-operatives may be approached from many different political angles. We are broadly left leaning in our co-operative, however I am the only Marxist Leninist. There are a few anarchist and socdems, but some of our ex-members were openly Conservative and viewed worker co-operatives as an extension to being “self-employed” or “running a business”, rather than being worker centric. There are also a lot of libs who like co-ops, but also lack the materialist and class analyses of other things and can’t break out of the “everyone should just form a co-op” mentality (note: this is less a reflection of my direct colleagues and more something that becomes apparent when engaging the rest of the worker co-operative or broader co-operative sector)

I would never discourage comrades or workers from forming co-ops, and my co-op’s structure, democracy, and staff compensation levels have allowed me to frame discussions with non-radicalised friends and colleagues in other organisations to e.g. direct them towards unions or get them to start questioning how the money they make for their corp is a lot more than what they receive in compensation. As noted, they’re a tool for damage control and for demonstrating the labour theory of value and illustrating how corp structures are oppressing even relatively well compensated workers.