Substrate comparison for germination - update

In a previous video here:    • Comparison of substrate types for ger...   I set out to compare two different substrates for germinating cactus seeds. Now that two months have passed I have some results. The comparison suggests maybe the free-draining, non-nutritious substrate is slightly better but it's way too small a sample to be sure. Echinocactus Grusonii germinated well in both types, Astrophytum Capricorne showed better germination in the non-nutritious soil and the Gymnocalycium Damsii seeds were a disaster. My conclusion is that it probably doesn't make a lot of difference at the germination stage, but I may stick with free-draining non-nutritious substrate in the future simply because that could avoid needing to transplant them when they are a little older.