See my review of our full day sailing trip we booked through Opcija Tours here:
It was fantastic, but note that Opcija is a tour company which does not themselves operate the sailing excursion. They paired us with a great sailing provider.
In addition, our experience with Opcija itself was fantastic. Damir was very responsive to all of our emails. The deposit process (via credit card authorization form) was simple and went smoothly. On the day of our tour, we found our way to Opcija's office inside the old town (a little tricky through twisty narrow not-always-clearly-signed streets, but use the map on their website!) about half an hour before our tour in order to pay the balance of our cost. They were super-nice, and even let us borrow their printer to print one important document that we needed for the next day. (Thanks Damir, and sorry for the paper jam!). They told us about a very interesting wine-pairing course for that evening, but we didn't end up having the time to do so. I believe it was about 230 kuna to sample wine from 4 different Dalmatian regions and have appetizers paired with each wine. Contact them for more details as we did not actually end up booking that tour.
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