Medium is perfect for me, I am not going to mess with it. For a lot of people getting the most bottom time is important. For me when diving on my own boat or friends boat, 10 minutes just doesn't matter to me. Cause if I want to stay down longer, I will just go up, eat a sandwich and have a coke, grab a new tank and drop again.
That's a good attitude. We've disagreed about a bunch of stuff over the last couple of weeks, but I'll give the thumbs up when we agree, as on this.
There's lots of info about the various models used by computers, and the point of a recreational mode is so that you don't necessarily need to drill down into theory. So, I'd just say that next time your blown out on some trip, maybe worth read. In the meantime, I will point out that this is a good attitude to take. No sense pushing the limits, especially when you're doing lots of dives.