I struggled with the authoritarian culture within Product Management. Meetings were nearly always dictated by the most senior employee in the room and dissenting opinions weren't taken into account. It's also a more traditional company where time logged on the clock accounts for more into someone's promotion potential than performance (hence the cooperative vs. cut throat).
If you're happy at your current band level and want a decently laid back culture, I think Entrust would be great. If you're trying to progress your career and push the envelope, I don't think you'll find the experience to be worthwhile. The company is growing at a slow pace and is trying to pivot from Physical to Digital--it ended up that someone had to get fired/quit for a new promotion to open up.
Although not perfect, I think that my time in Product Management prepared me well for the next portion of my career (outside of Entrust). That said, I would not feel the same way if I was in Marketing. Entrust does not offer much true marketing--instead nearly everything (from creative to analytics) is outsourced. Frankly, the marketing positions are more along the lines of Project Managers than anything else. And Marketing Leadership seemed very 'fluffy.' No data driven decisions but rather the 'gut feel' of marketing leadership.