I was surprised when my friends planned a full day for this but ultimately, we stayed from just after open to close, and relatively easily! We did not do a long wait for FOP (I waited 45 minutes on standby) or any other rides and we did not have a huge amount of downtime. We did do the Nemo show, which is almost 45 minutes. Around 4pm or so, after using our last FP at the rapids, we did wonder if we'd make it till 7pm for ROL, and because we wanted to catch the show, just added another FP for the safari, as we had enjoyed our morning one so much. That helped fill a bit of time, as we stopped for a Dole Whip on the way from Asia, did our trip and then had dinner on the way back toward the ROL amphitheater. So, I'd say yes, it is a full day park, especially if you plan to enjoy the animal exhibits, all of which can take up some time (up to you just how much on all but the safari). The Gorilla trail, the Tiger Exhibit and Rafiki's Planet Watch are all linger at your own pace type things and can fill as much time as you do, or don't, want them to. And this was all with basically completely ignoring DinoLand all together (my friends hit up a short wait ride there while I was FOPing, but that's it). With kids, that's probably not something you'd want to do!