I took the SDI solo course for 2 reasons..First off to me it’s all about self rescue and survival. If you add that to the rescue course it can only make one a better all around diver. And being the best diver for you and your buddy is really what it boils down to...Second there are a few times that just being on your own is great as well. I find it very relaxing to just swim around at my pace with no other worries. I dont solo dive all the time but I have the training and feel it made me a better safer diver. In the long run thats what its all about