I have less than $280 shipped in this exact same setup and I have side plates with mine , and all my plates have been sprayed with truck bed liner to prevent spalling . Lots of other options out there if you just take a look , Keep in mind 1/4" AR500 is not going to stop AP rounds
Back when I was on the job (that sounds like I'm so old) (holy crap I just added it up and it's been 20 years. Damn it I would be getting close to retirement.) sorry ADD moment. Back when I was on the job we had to provide our own. Back then they suggested you buy one with a threat level as high or higher than the gun you carry. They were pretty heavy if you wanted to stop anything more than a handgun. I paid around $700 it would cover up to a .44 we still had officers that carried .357 so I figured I wanted to be covered even though I was "one of the 9mm kids".