Prós
RTCS (Raytheon Trusted Computer Solutions) definitely has a great culture and has been quite successful in some areas and there is definitely a lot of good talent working for the company. The gender balance among employees is remarkably good (especially for a startup) and this is true even within the purely technical side. The acquisition by Raytheon will continue to address some of the minor annoyances of being a small company (travel reimbursement processes are much better now).
Contras
While the acquisition by Raytheon brings many opportunities, it is quite easy for the culture to be lost - the realignment of products / groups between TCS and the rest of Raytheon may have made sense at a corporate level, but I don't think it did TCS any favors. While some aspects of large company operations are an improvement, there is also a lot of administrivia and overhead introduced as a result, and it may be harder for TCS to attract the same types of employees as it has had in the past.