with a Stofen.
why? for outdoor shots, it's not like the flash is going to bounce off of anything... a sto-fen would just cost you flash power.
People shots, fill flash, softening, don't see how your going to be able to us a bounce flash much if at all at Disneyland.
I'd also use manual and dial it down a bit too for close-ups
That's the point. the sto-fen Omni Bounce is exactly that: it simulates a bare-bulb effect, throwing light everywhere, so it bounces off of every available surface. It's not a softbox, and the apparent flash head size is the same, so you'll still get the same shadows you'd get without it. You're just throwing light in other directions that will be wasted instead of landing on your subject. Might as well not use it and just use a bare flash head. Or, get something like a Lumiquest softbox that goes onto the flash head and softens the light, if that's your goal.
No doubt, a little soft box on your flash head would be much better but a little bulky for walking around Disneyland. And of course the Stofen diffuser is not ideal but I'd rather have it than direct flash for a little fill-in flash.