Prós
This is a company that values engineers very highly. Jack Little is an engineer and his DNA shaped MathWorks more than anything else. The work is very interesting and you can be rest assured that no matter what project you work on, you will have impact on the customers. While it is not a sweat shop, you can find many MathWorks employees to be highly motivated to make a difference. Managers are grown from within and they typically work much harder than the people who report to them. For example, my manager usually comes in before everyone else and frequently the last to leave. Not to mention the nights and weekends where he can be counted on to fight fires, reply to urgent emails and even fix bugs. In general, this is vastly different from other companies where my friends work where managers are just paper pushers. It is just fantastic to have your manager be as strong technically as you are. Being private and profitable means that MathWorks does not have to flip-flop to market gyrations. We can think and invest long term. There are quite a few projects I know of where millions were invested over the last few years with huge teams and these products are not paying for the salaries of even half of the team. I can see that Jack persists with these efforts despite the steep initial cost with eye towards building products for the long term. MathWorks has a fairly non-political and rational workplace. While ugly and open dissent is discouraged as it is often counter-productive, true dissent based on sound technical reasons is not only tolerated but encouraged. I know of at least three different technologies that emerged over the years purely because no one said you only have to do it one way. While this can be inefficient at times, it often paid handsome dividends by creating some really disruptive technologies that no one thought were possible initially. The pay is very good and very competitive. While you may be able to make marginally higher money elsewhere, it is hard to match the quality of life you can get here.
Contras
MathWorks has a six-monthly release schedule which can be very taxing at times. Getting big things done is a challenge due to a fairly large and complex code-base. As I mentioned earlier, engineers are highly valued. The other side of this coin is that they are also highly accountable for the success/failure of the products. Sometimes, it feels like every new process, rule and regulation applies only to the engineers and not marketing or other functional areas. For example, the quality initiative that we started a few years ago spawned myriads of new processes and guidelines and almost all of it is dumped on the shoulders of engineers. Office space is getting to be ridiculously scant. MathWorks started off with the noble idea of offices for everyone. However, we could not scale this well with all the growth we have had in the last few years. We now have cubicles in the famed idea zones and people sharing offices etc. We should have planned better for this.