I don't claim to be an insulin afficionado, but I have run it a few times. I'm curious as to why you intend on running it the way you have outlined?
I would only use insulin post-workout. That's when your muscles are screaming for goodies in the form of glycogen, protein, and creatine. More nutrients will be shuttled into the muscles when using it post-workout; conversely using it randomly throughout the day will increase the likelihood that more of these nutrients get stored as adipose tissue, even if your diet is clean and close to perfect.
Believe me, if you intend on using it, only use it post-workout.