I think AIS is an essential part of the safety gear. In fact I think all entries, whether or not equipped with radar, should be required to carry a transponder type 'B' unit and keep it turned on for the entire race, once beyond the ocean's demarcation line (inside the bay, forget it). Energy consumption is tiny. There are a ton of options now. Cost is really not bad, and it is still dropping.
I think one of the things that made AIS so valuable for me was the ability to configure alert criteria and see a graphic display. I used a dedicated display by Watchmate because I didn't want to leave the PC on. It consumes practically nothing, has a totally configurable set of alerts, and the display stays off until a target fits the criteria you configure.
Adam said that Blue Moon was a ship magnet. I encountered many also. But even if just one ship in 2200 miles happens to find your boat while you're sleeping, wouldn't you want to know about it, and better yet, wouldn't you want the ship to "see" you? You can forget about them seeing your (required) radar reflector until it's too late, if at all. On both legs I encountered ships whose CPAs stayed around 0 nm consistently, until one of us changed course. When well offshore I would set the "CPA" alert to 2 nm. That would result in an alert sounding over an hour before the TCA (time to closest approach), which gave me plenty of time to track the ship and decide if a course change or hailing them was necessary. I also set a "Range" alert that had priority over the CPA alert. I wanted to know every time a ship was inside of 6 nm from my position whether or not it was on a collision course. I frequently hailed ships (by name)... I enjoyed the conversation even if there was no danger of collision, and when there was, they invariably agreed to change course so I didn't have to. Oh... and what peace of mind I had when I saw them changing course real time.
Paul/Culebra