Efficient Asset Handling in Bevy: Seeking Advice on Mesh and Material Management

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Hi, I need your advice on how to handle assets properly and efficiently.

I wrote a function that spawns a bullet entity on the screen:

fn spawn_bullet(
    mut commands: Commands,
    mut meshes: ResMut<Assets<Mesh>>,
    mut materials: ResMut<Assets<ColorMaterial>>,
) {
    commands.spawn((
        MaterialMesh2dBundle {
            mesh: meshes.add(shape::Circle::new(1.0).into()).into(),
            material: materials.add(ColorMaterial::from(COLOR_BULLET)),
            transform: Transform::from_translation(get_random_position())
                .with_scale(Vec3::new(BULLET_SIZE, BULLET_SIZE, 1.0))
            ..Default::default()
        },
        Bullet
    ));
}

The code above adds identical Mesh and Material entities to Assets<_> every time it's called. I'm wondering if the data stored in mesh remains even after bullets are despawned, potentially accumulating throughout the game.

When I searched for a way to handle these kinds of assets, I found some projects in which Handle<_> for those assets is kept in Res<_> and reused:

struct BulletAssets {
    mesh: Handle<Mesh>,
    material: Handle<Material>,
}

fn spawn_bullet(
    mut commands: Commands,
    bullet_assets: Res<BulletAssets>
) {
    commands.spawn((
        MaterialMesh2dBundle {
            mesh: bullet_assets.mesh.clone()
            material: bullet_assets.material.clone(),
            transform: Transform::from_translation(get_random_position())
                .with_scale(Vec3::new(BULLET_SIZE, BULLET_SIZE, 1.0))
            ..Default::default()
        },
        Bullet
    ));
}

From an efficiency standpoint, which approach is more preferable? Is there a more preferable way?