Well, you could get yourself a glucometer and check your blood sugar with each new food.
I did this a few years back and it was actually painless (virtually) and fun.
I'd do a finger poke and a reading just before I ate a particular food and then do subsequent readings at 15 minutes post meal, 30, 45, and 60 minutes.
A "good" food will take you from a baseline of about 70 to around 110 a half hour later and then bring you back close to your starting point after an hour.
Worst food I ever tested? Special K, the "dieter's cereal."
While Metabolic Drive protein is formulated to have a smooth curve, I'm uncertain as to what the bars will do. For sure they'd show a much better response than a conventional candy bar or protein bar, but it might not be ideal.