Can't speak for FireBeyond or dorian-graph but I too am running it on my regular, everyday iPhone 5 and have found it surprisingly stable. Any actual crashes s

Can't speak for FireBeyond or dorian-graph but I too am running it on my regular, everyday iPhone 5 and have found it surprisingly stable. Any actual crashes seem to be a result of doing too many things at once, particularly during an animation (eg: close out of an app and double-click for multitasking before the animation is finished). The crashes seem to cause a restart of the Springbord app rather than a complete system reboot, so it comes back within 10 seconds and hasn't lost any data (it even keeps the same song playing in the background).