Our Rough Guide to Croatia recommends Jadrolinija, Blue Line ferries and SNAV Croatia Jet. The main difference is that Blue Line and Jadrolinija run year-round and the journey takes a whopping 10 hours. SNAV run a summertime high-speed service that is less frequent, but takes only 4hr 30min. Which one will suit you better probably depends on your time and budget constraints. I’ve travelled with Jadrolinija and they’ve always been reliable and comfortable.