Night Train Zagreb to Split Help
 

Hi, I will be travelling on the overnight train from Zagreb to Split with my family in August and was hoping someone had experience of this journey and could advise on the following; how comfortable is the journey, the difference between the couchette carriage and sleeper in terms of comfort and cost and how we can book the Sleeper before we get to Croatia (seats and couchettes can be booked in advance, it seems sleepers can't). Thanks all.