Campaign Idea - Fantasy World as an alien planet

I was thinking about this campaign idea for a while. What if PCs in a fantasy world, are actually humans sent to a distant, alien, but earth-like planet on a mission?

This idea first occurred to me when reading Polish fantasy book series - Pan Lodowego Ogrodu, by Jarosław Grzędowicz. In the books, the main character is sent to alien planet to find some missing scientists sent there by earth years before. This world, is inhabited by human-like creatures (minor differences in looks), who have achieved early middle ages (maybe late antiquity) technology level.

Earth is abiding laws similar to prime directive, so they make the main character look like one of the inhabitants and equip him with appropriate weapons and clothing. Communication with Earth is non-existent.

If you ask me it is a great idea for a RPG campaign! It gives the players a reason to stay together and explains the out-of-game knowledge the players might posses. This can also explain why PCs are leveling-up quicker compared to other people (nanites?). It also makes for a great GM tool - you can easily introduce strange creatures and alien vistas to the world. Players can have limited intel about the layout, customs and creatures of the world - this would make for a great Sandbox style campaign. Where focus is put on exploration and discovery. Maybe their mission is to map a portion of the world (Hexcrawl?). 

This idea can be summed up in few points:

• Players are humans sent from technologically advanced Earth on a mission.
• Players will look and be equipped accordingly thanks to the Earth's technology.
• Communication with Earth is limited or non existent.
• The planet is a low-fantasy world - magic is rare (and unexplained by humans).

I might tinker with this idea more and run in the future on Savage Worlds.

What do you think? Do you know of any similar campaigns?