I have the PB Alpha Elite IIA concealment vest. It's worn under a traditional uniform shirt, with plenty of Dept. Issued flair attached to the shirt. Vest comfort is top notch compared to my previous ABA concealed vest.
Only complaint, and I don't think any concealed vest/flair combo would solve this issue, is shouldering a rifle. My name tag and all important CIT pin fall off every time I bring my SOPMOD stock to my shoulder. Mostly the CIT pin. The rubber butt pad grabs my flair. More of a uniform than vest issue though. For patrol, our shirts look like we are ready to invade Poland. Pair that with traditional uniform pants, and we have a very "functional" patrol uniform.
As far as vests go, the PB Alpha Elite is hard to beat. Thin, flexible, and comfy for a vest. Can't vouch for its ability to stop incoming rounds, and hopefully I'll never have to. Dyneema fabric appears to be GTG from my research.