Hi Freak.... am finding 5:2 ok(ish), though it is making me quite obsessed about food! I find myself noticing the calorific content of everything I consider eating, which I have never done before....
I think if I can manage it, I will give it a couple of months. I tend to do my 2 days during the week and have found that if I get up, have a cup of tea, get the kids off to school, then come back home, shred and eat my low cal breakfast (poached egg on sourdough toast) afterwards, then I'm ok. I can have miso soup early/mid afternoon, numerous cups of herbal tea and water to keep me going, and then supper in the evening (salmon + vegetables or salad for instance). I do still feel hungry when I go to bed, and often wake up very hungry in the morning, but it is do-able.
I think it was Mimi Spencer who said once you get into it, you don't miss eating, but I have not found that to be the case at all! I obsess about what I might be lucky enough to eat when it's all over..... 
I use mfp too, and like you, to organise my day in terms of what I am going to eat that day, and only restrict the calories on my fasting days.
Part of me just thinks I ought to get a life and stop thinking about all of this so much (!), but then I found myself in a M+S changing room this morning, and OH THE HORROR!!! Not blessed with flattering lighting or a bit of room to stand back and lessen the blow, it was rather a shock! Legs like sausages and a butt like a slightly deflated balloon.....
(sobs)
So, am ordering ripped now, and will shred (l3) once I have cleared a load of work from my desk.....
Admire anyone who can run. Am contemplating couch to 5k.....