When I changed my cat over to raw I didn't bother with transitioning (except supplementing the meat until he started eating bones). He loved it so much and it seemed so natural that I just went for it, and he was fine, no stomach problems at all.
I would say though, be careful with the minced meat. Because it's minced it has a bigger surface where bacteria can grow, hence more potential for stomach upsets. So if you are considering feeding raw on a regular basis, switch to chopped up pieces rather than mince
