The original has the strong point of being the default classic Plugsuit, while the Test Plugsuit has the strong point of being in part a relatively well made Fan Servise product that definitely looks more modern compared to the original Evangelion Unit 02 Plugsuit, and that's not to mention that it's somewhat revealing (or provocative, however you want to put it) as well without entering the threshold of what could be labeled as Explicit/Hentai.
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