Re: AW Bolt knob
I know of at least one user who has replaced the AI knob, although I don't have any deeper details.
I was training with the AE yesterday and had several rapid fire stages. The best think I can say about it was I never once thought about the knob. It did what it was required to do.
It's your rifle and if you want to change up the knob, so be it.
I would just suggest you spend some time in deep meditation concerning the change. No system will be perfect for all users. However of all the AI's ergonomic quirks, I don't think the bolt handle comes close to the top of the list.