laravels polymorphic relationships performance

Does anyone have any experience with performance of polymorphic relationships in Laravel? I need to have a settings tables for few different models, polymorphic relationship would be good here, I am wondering about performance, is it as good as if each model had its own settings table?

Settings table is simple and this is how the settings table would be like:

        $table->increments('id');
        $table->integer('foreign_id')->unsigned();
        $table->string('key');
        $table->string('value')->nullable();

I would shave off few tables that are needed for each models settings, just wondering if there would be performance issues using polymorphic setup?

via Chebli Mohamed