Pros
A great company if you want to learn Winforms, VB.NET, Fox Pro and SSRS reports. You could end up spending most of your time doing that. Upgrading has been promised for years and continues to be promised. An excellent company if you like using proprietary versions of common coding libraries. They have their own highly custom versions of many common and free technologies. You will not find much of their stuff anywhere else. This is a great advantage because it may provide job security to those who spend the years required to master the inhouse technology. On the other hand Google search may return zero results when you don't know how to do something. Great opportunity to work in databases with many triggers and stored procedures that are thousands of lines long - a fantastic way to enhance your SQL debugging skills. It is also a wonderful place to work if you want to spend 90% of your time learning the company's custom interpretation of the vast set of Medicare Billing rules, etc. If you enjoy working in legacy land, knowledge silos and undocumented custom technology this could be the ideal place for you. Senior developers at this company are extremely hard working and often do overtime. There is an every man for himself attitude (training is minimal) so you should feel good in the knowledge that every developer here is the best of the best because they have survived everything that was thrown at them. Also due to excellent management on a detailed level any non-performers are routinely dismissed without warning. Senior devs are usually paid $130k-$150k on sign up which is above the average of about $120k for the area.
Cons
There is a very high attrition rate but this only because those people could not keep up with the demands of the work or were not satisfied with the custom and legacy technological choices. The company is probably best for people who have no children or undemanding spouses. As a senior dev you may be expected to provide 1 week of 24/7 production support about every six weeks on all of the company's products whether or not you know anything about those products. If you are highly creative and enjoy learning new technologies or simply like to stay up to date with newer technologies then this is probably not the place for you.