I did FoP at RD twice last week and while my experience wasn't terrible (below), I would ask myself the following questions: do I like being smashed together with hundreds of other people in what feels like the starting gate of the NYC marathon where the goal of the race is to trample everyone in your path to "win" your objective of standing in yet another line? do I feel that personal space is overrated? what is the maximum population density you can achieve for a one square acre plot of land? how ruthless can people be when dealing with the old, the young, the weak and anyone silly enough not to be moving as fast as they are? is it better to go around or leap over that stroller that someone in front of you is foolishly trying to use as a moving blockade? just how claustrophobic am I? do I think that people yelling and screaming at their families and friends to hurry up is an entertaining part of the pre-show? to refresh myself for the ride, can I watch the entirety of the 2.5 hour Avatar movie while waiting in line (I'm going to start calling this the "Avatar" rule - if the wait in line is longer than the actual movie on which the ride is based, I will have to say no - I've also got my eye on you 7DMT)?
In all seriousness, most of the people at RD were anxious but not rude. Most. You'll see some very stressed and intense people, however, so go in knowing that it won't be the most pleasant experience. As for my two experiences:
Day 1: arrived at AK around 7:45 for a 9am park opening. Lines formed at the entry gates and a mass of people all the way back to security - most everyone there for Pandora. Gates opened at 8:15 and an orderly exodus towards Pandora (the speed, regulated somewhat by CMs, was about "hardcore mall walker" level - a few sprinters, but they all got stopped by some pretty vocal CMs as they got towards the front). Wait on the bridge to Pandora for 15 minutes - this was the worst part as the folks coming in later kept trying to surge towards the front - if you've stood close to the stage at a big concert, that's what this felt like. Pandora opens at 8:30 and the CMs funnel us into the line for FoP. I ended up about 25 yards from the official entry for the ride. Ride was up and running shortly thereafter and the line never stopped moving. I was inside the "cave" by 8:40 and in the pre-ride chamber by 8:45. Except for a technical glitch in the chamber, I would've been off the ride before 9 am. I got out at 9:10 and the posted wait time then was 110 minutes.
Day 2: arrived at AK around 8:20 for a 9am park opening. Both the gates and Pandora were already open, so I went through and got in line (this time hundreds of yards away from the ride's gate and closer to Africa than Pandora). On the one hand, I skipped the nastiness of the PPO crush to get in first; on the other hand, the wait was longer. The line moved in fits and starts. People complaining about line jumpers (although none that I actually saw - I suspect some people went and rode NRJ first before getting in line with their families/friends waiting for FoP). I got into the cave around 9:20 (posted wait time was 90 minutes) and was in the pre-ride chamber by 9:35 (more technical glitches - I'd have missed most of the pre-ride video if I hadn't done it earlier in the week). I was off the ride at 9:50.
Even though the wait on Day 2 was longer, I preferred it to the stress of Day 1. The "crowd psychology" of waiting at the gates and entrance to Pandora was worth trading for some extra time in line on Day 2. I still think doing FoP early morning is preferable to waiting hours at midday (the ride is not THAT good in my opinion), but I've taken note of the people who have suggested trying in the evening as a "better" experience.