No offense intended here, but you do a 2 hour half, right? For slower runners, a fast field may mean no water left at the aid stations (if they are even still , no medal, no finish line, no refreshments left, anything. Not to mention the feeling bad part, and the faster folk who offhandedly say things like, I could *walk* that pace.
I did a local race where my friend and I were close to last, we didn't see anyone in front or back of us after about mile 4-5, and it was lonely and quite frankly, didn't feel good. I don't want to repeat it.
Everyone is different, though, so some people might be okay with that. I'm just, well, not.
Now that I got that out, for anyone reading who is a back-of-the-packer, Disney races are *awesome* for that. Tons of support, aid stations, and you will not be alone at the finish at all. I have done the Princess both of the last two years with friends that finished 3:40+, too, so I have been there to see it.