Is it plausible to depict the Segmentata using armor upgrades?

[Ludens]

As far as maintanance time, its been the same for any professional fighting force. We had to maintain our rifles, mortar systems, vehicles, personal equipment, etc. It didnt matter if youd been on ops for months, or a 20 mile hike all night, the gear still had to be cleaned and maintained before we can call it a day.

Except that the Romans didn't have electrical lights by which to clean it, so they couldn't do it after sunset. That's what PVC is arguing. I quite agree with your other argument, though. It must have had some benefit if the Romans used it for so long.