Safety and luggage

I will be traveling with my wife from Guilin to Hong Kong. In my trip we're taking a train to Shenzhen North Station, then pass through Futian Check Point and then take East Rail Line from Lok Ma Chau to Hung Hom Station. We'll be carrying quite big back packs each of us and two baggage (size is like the one airlines allows you to take with you in main cabin). Is is safe and common to take these rail transportation with such baggage? I appreciate your suggestions and comments.