Pros
I worked at helloU for around 6 months before leaving to start my own business. The environment was very much work-hard-play-hard which promoted a great atmosphere and working environment. Some highlights: - Entrepreneurial atmosphere: everybody has a say in the direction the business takes - Quick opportunities to advance: very meritocratic, if you want to learn about a different part of the business or even manage a team (and you're good enough) it'll happen. - Fast paced: constantly innovating the product and thinking of new ways to meet their market. I've since been through an accelerator for my own business and I'd say I learnt just as much in the 6 months I was at helloU. Perks are pretty good too, within 6 weeks of joining we had our christmas party.... in Barcelona.
Cons
Don't know if they still do it, but instead of destroying you for small mistakes like being late, they have various penalties such as buying pastries for everyone. Basically gamifying simple things which is kind of cool.