But the thread was started on the question of how many TYPES of armor they have used. Not "Are they the originals" or "They are the same one".
They are UPGRADES and IMPROVEMENTS! It is MUCH easier to make a new armor plate than take the old one apart, and add the stretch material to the whole thing. You have to think of structural integrity on that one.
When a new type of metal or plastic is synthezised, you don't take your car in to be upgraded to that material. You buy a new car. Same for armor. You don't take shoulder pads off, change the plate, and hand it back off. You buy a new one that you know will be off the best quality.
And who said the armor was all made of the same stuff and served the same purpose? Think of modern day armor vs medieval armor. Modern day host bullet proof vests. They serve a different purpose than medieval suits of armor. BP vests stop bulltes,a nd are made of a steel alloy and cloth. Medieval armor was made of steel, plain and simple. It was designed to stop swords and javelins. Don't forget about leathers. Riding leathers are a type of armor. They protect you from road burn when you fall off your bike. You can't add leather to iron and say it is the same armor. It isn't. It has an upgrade, serves a different purpose, and thus, is a whole new type of armor.