I think it is fair to say that most N American cruising boats have pressure cookers. We cruised for 3 years without one and have recently added one.
When we were preparing to cruise, the reasons that people gave for needing a pressure cooker just weren’t compelling to us. When we were reading it seemed like people recommended a pressure cooker primarily to save gas and to reduce heat in the cabin. We have a 20lb propane/butane tank as our main tank and a 5lb for the BBQ. We go 3 months between propane fills -- cooking three meals a day, coffee and tea, and baking whatever we like. We don’t have a problem with propane lasting a long time and in general our propane costs are very low compared to our gasoline and diesel costs. As for reducing heat, the only time we make a lot of heat with our stove is when we bake which we wouldn’t use the pressure cooker for, and pressure cookers aren’t heatless devices. In short, we didn’t buy one because we weren’t sold on the benefit and they aren’t cheap.
Second, faster dinner preparation. We realized how quickly we could cook large quantities of things that normally take a long time. In particular, we realized we could cook two favorite foods which we rarely cook because of the length of time they take: a whole chicken in 20 or so minutes and/or an entire pot full of whole potatoes in less than that. THAT was impressive and sounded like a game changer.
Third, we have found that we have cut costs a little with the addition of a pressure cooker. So far in our travels, we have found whole chickens to be regularly available and inexpensive and now that we have the pressure cooker we can take advantage of the low cost to buy two whole frozen chickens when at a grocery – cooking one right away and the second in a day or two when it defrosts. Now that we have a pressure cooker we also cook a lot more dishes with inexpensive dried beans than we used to which is a health gain as well as a financial gain. Plus, the ability to quickly cook beans opened up some dishes we enjoy but weren’t cooking (curried lentils, chilis, etc.).
You don’t need one to cruise – clearly – but there are me reasons to have one that weren’t articulated in anything we remember reading while prepping.