Callidus was an excellient place to work. I would highly recomend it to anyone. There is pleanty of room for advancement and it has some of the brightest people that I have ever worked with.
Callidus is a great company to work for in the sense of people. The managers are great people and your colleagues tend to also be friendly and supportive.
Cons
The cons come into the picture with the corporate aspects. Callidus used to be a private company and since the Honeywell buyout, corporate politics have taken a front seat.