We bought the Groupons to sail on Fame and had no issues at all. It clearly stated on the instructions that they did not take reservations for groupon holders, and they laid out their hours of operation and even the fact that in inclement weather they could call the cancelation closer to sail time. With all this in mind, we planned our day knowing we had to be flexible, we got their 1.5 hours before sailing, easily made our reservation at the both and went on to have some drinks and appetizers at Victoria Station.
The boat was smaller that I thought but ended up being just perfect, it was not crowded, maybe about 15 guests and plenty of room for a leisurely sale around Salem Sound. They did give a bit of a history of the boat and surrounding area. For those with kids, they gave a chance to help steer the ship and bring up the sails. The crew was very friendly, and nice. The ship had a bathroom below and sold snack and drinks including beer, wine and magheritas.
It was a great way to spending the afternoon, which we continued on with some local shopping another local bar for drinks and dinner