Steff,
I use Mother Cultures every day. I don't do it for the price. I do it for the "ease" and consistency, which translates to better cheese. It is very difficult to make minor adjustments with dry culture. How do you reduce your starter 1/16 tsp??? I don't know anyone that can measure that accurately. Maybe if you were using a gram scale. OTOH, it's easy to remove 1/8 cup of MC. As a pro, I can't imagine going back to DVI.