Well if you want to do an experiment, you need to have a baseline to compare it to.
Have you had a successful grow? If so, with which what nutrients? If multiple nutrient lines have given you success, which one gave you the best results?
In my opinion, anything you've shown to be inferior should be thrown out. I would only use the best product I had on hand.
If I had multiple products with no idea which one was the best, I would just try one out and measure the results. Then try another set of nutrients on another grow and compare results to previous grow. Toss inferior product.
Just remember that if you really want to do a sound experiment you should be isolating variables and that means everything in your grows should be the same except what you want to compare (in this case, nutrients).