Pros
I believe that many people go their entire lives without finding a job that truly makes them happy. I had that at Quintiq. The culture of the company is that of "work hard, but be happy while your doing that work". I was surrounded by creative, intelligent, motivated peers who were eager to provide me with whatever help that I needed to achieve my full potential. I was proud of the work that I did and was able to see immediate results in the companies that used the software that I created for them. It felt good to brag to family and friends about how the code that I wrote directly influenced efficiency at some of the largest companies in the world. The work is exciting and fast paced. A typical day involves sitting in front of a whiteboard with a few peers, and trying to design a solution to some logistics puzzle. As a software engineer, there are a wide variety of jobs that you could have. For example, somebody has to write the code to make error codes show up correctly on a cable box. I can assure you that this job is the complete opposite end of the spectrum. The problems that you will solve will require you to be creative and solve puzzles. Your full time job is to solve the types of problems that you read in brain teasers. It's fun!
Cons
Quintiq has a very flat structure, which is great because you work among your equals. As you gain experience, you will be given additional responsibilities. But, your official title won't change. Some people want to move up a structured managerial latter as they put in their time. I would say that Quintiq does not follow this structure. Sales cycles are battles of attrition, but the rewards are huge. This means that the difference between a good year and a bad year is often whether or not your business unit had a single sale.