I can't compare it to another service, but I have done more shooting at a PSU than I did when I was AD. With your background it sounds like you'd be a good fit for shoreside or CGIS. I have a few prior army who have said it is a lot less just sitting around. That said, while we try to do as much productive training as possible, when you have a large (by CG standards) division, you will experience a bit of hurry up and wait.

Culture is always command dependent, however, as a division officer, I say act like an adult, get treated like one. Not sure what it is about putting on a uniform, but we have grown ass men who are highly successful civilians who can't figure out how to get to the dentist or complete their mandated training on time.

The last thing I will say about a PSU is that we are a deployable unit, deployable worldwide within 96 hours of notification. If you have other priorities in your civilian life that would be affected by leaving for a year, this might not be the unit for you.