We did the safari in March 04. The dinner at Jiko was wonderful! I always say the whole experience is the best money I have ever spent at WDW.
As far as the experience being different.. yes, it is for several reasons.
For the dinner, you are seated with the other folks from your safari. I wasn't sure I would like this, but we had a great time. There is plenty to talk about .. the safari itself, WDW, other restaurants.
The best part of the safari dinner was getting to try all the different foods. There were several things we would not have order, but they served it so ater trying it, we found out we did like it. We had 4 appitizers, 4 main dishes and 4 desserts. The chef coming out before each course was great. We are not big wine drinkers so getting the taste the S. African wines was nice.
As far as tipping, the tip was included at dinner. I am trying to remember if we tipped our guide and I am not sure. She was wonderful though. Her name was Karen and she had worked at AK since it pre -opening and then moved to AKL before its opening.
As far as dining there alone and with the safari, I would not do both on the same trip. But we often go back to Jiko and fondly remember dining there after the safari.