Absolutely, just make sure to mark it as such in the event submission so players know what to expect, and be aware that it will come with a ticket cost.
The benefit of the First Exposure Playtest Hall is density, reliability, and structure, basically. A large group of potential players are gathered together and the FEPH staff will attempt to filter them to suit the needs for your game. You'll also be working near a bunch of other creators, and the FEPH partners in the room cover groups like printers that can help you with the next step of the project, too.
Outside of the FEPH you're on your own. Depending on the scale of what you want to do and where your game is at, that might be just as good or better, but it really depends on what you are going for.
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