Is there any concern that object id references are made by string and not ObjectId?

[jmshelby]

I noticed, that when relationships are used, you're setting the referential object id as as string rather than and ObjectId type. Is there any concern with this route, as far as speed and optimization?

The link Here seems to imply that references should be stored as this ObjectId type, since it takes up less space and is faster to query by.

And here is what I see in my database, showing that the type of the reference 'player_id' is stored as a string rather than an ObjectId:

> db.player_pool_activity.find().pretty();
{
    "_id" : ObjectId("530596439e8ff6791a8b4567"),
    "player_id" : "530591529e8ff64f198b456b",
    "updated_at" : ISODate("2014-02-20T05:44:35.942Z"),
    "created_at" : ISODate("2014-02-20T05:44:35.942Z")
}

[jenssegers]

I tried using ObjectId's but it turned out to be a pain in the ass for Eloquent and the relations.