Pros
Consero is a great place to work if you are a self-motivated individual who appreciates macro-management vs. micro-management, and are interested in developing skills within and outside of your immediate job function. Because it is a start-up, you are expected to work hard during work hours. If you are someone that wants to float by, don't bother applying, that's not what a start-up is all about! My advice? Go work for the government.
Managers are very transparent about the job duties, and like any other company, you have to work hard, put in a lot of effort and demonstrate a good attitude to move up the ranks and gain more responsibility. Whether you move up or stay in your position, you develop tremendous customer service, project management, sales, communication, and marketing skills. Not to mention that you singlehandedly have the opportunity to run an event for some of the most powerful and successful executives in the country and abroad. The connections you make and opportunities you are given are very unique. My resume is 50x stronger now then it was before I started working for this company. It's unfortunate to see such negative reviews but it tells me that you weren't willing to put in the work. Note to those people -- don't apply for a job at a start-up!
Cons
Cold calling and sales is not for everyone. And, that's ok. Pay attention to the answers given to you during your interviews and prepare questions so you can determine whether the position is a good fit for you before committing.
Most positions are salaried plus commission-based hence, you have to work hard to make money. Not unheard of for sales-based positions.