If money wasn't an issue, I'd pick the Sunset Safari any day! It's a much smaller safari, most likely with no kids. They do have a minimum age limit for kids on the sunset and at those prices it doesn't seem many people bring kids - so there's a good chance of an adult experience. Also, dinner at Jiko vs a busy crowded buffet just sounds alot more appealing! And, you don't have to get up before dawn ;-)
The Sunrise Safari is pretty cool, and I booked it again for Thanksgiving morning. It's alot cheaper, but still $110 for 2 adults for breakfast....and it's fairly crowded and lately has had a lot of little kids.