Index or middle finger on homing dots F and J?

Hello, I received my beautiful Model 100 yesterday. Now I find myself trying to type on it and to my surprise I find it way more difficult than I anticipated…but ok - it’s early days.

On a normal keyboard the index finger rests on the F and J keys. On the Model 100 as probably also the Model 01 I can see that this works, but somehow I get the feeling that the ergonomic layout would favor having the middle finger on F and J so that all keys can be reached more easily. But that of course means my brain not only has to remap where keys are, I also to remap which finger is responsible for which letters - twice the work.
Curious, how do experienced keyboardio users prefer placement of index vs. middle finger on home keys F and J?

Index on F/J is what I’ve been doing for the past couple of years. Using the middle finger for them would require using my pinky for not 2, but 3 columns, while my index would be responsible for 2, rather than 3. The index finger is usually considerably stronger than the pinky, so more columns for the index is better than the other way around, in my opinion.

I also find it easier to reach with the index finger inwards, than with the pinky outwards, not to mention that my index is also longer than my pinky, so that makes it easier to reach more keys, too.

Our design intent was that index fingers go on F and J. But also that PROG/LED/ANY/NUM are not meant to be touch-typed. But type however feels the most comfortable.