Here are the few downsides I see which are not offset by their corresponding positives:
1. Mitratech has not always treated employees with the respect they deserve after mergers/acquisitions.
2. The company is owned by private equity, and the quality and decency of the leadership largely depends on the priorities of ownership. This leads to a significant degree of job insecurity for anyone potentially "redundant." It also leads to some staffing and resource shortages.
3. While I doubt that Mitratech will be "digital roadkill" anytime soon, the leadership priorities often seem a little too reactive; I often felt that we were just "treading water" in terms of quality and innovation. Enterprise software is by its nature boring; it's hard to stay enthusiastic in that sort of environment.
4. You are working (directly or indirectly) for lawyers. Google "lawyer jokes" if my point here is not clear.
5. Pay and benefits could be better.