Everybody fears a roll-over. Some members here have experienced one, and seen one too. But they are not as common as you are led to believe. In my 36 off-road drives with Carnity so far, I haven't seen one or even been exposed to a situation which may have potentially become one. I've felt challenged but I've never felt afraid. This is not to say, that it can't happen. The marshals and the center-forwards (depending on where you are in the convoy), will always take the most reasonable line. You are also permitted to not attempt anything that you're not comfortable with. We don't shame anyone around here - because this isn't a race and we're not staging the next production of Mad Max
Secondly, in most cases, a roll-over or any slope-side accident is caused when drivers continue to fight against the most powerful of natural forces - gravity. If you learn to read how your car behaves, its weight, its dynamics, how much or how little throttle you need, what the sand is telling you, and ultimately how all of it combined is reacting to the gravitational force, you will master the art of driving your car at the limit - but safely.
I regularly drive on track at the Autodrome in addition to the off-road drives. And I have insurance covers to protect me and my passengers first. The vehicle is secondary. As expensive as it may be, it's replaceable. But if a comprehensive cover gives you the peace of mind, do go for it. But think of it just as the name suggests - "cover". Don't let the fear of a roll-over prevent you from taking calculated challenges to push how much better you can be. And don't let the learning of all those drives send your confidence into overdrive that you fight gravity, and risk it all.
See you on the sands soon