Me too for the vision issues and definitely the self-threading needles are the way to go!
Besides, I find holding it awkard/clumsy to hold the threader, needle and the thread.
There are a few different types of these needles, so if you don't like one, try the other.
What I find is sometimes the thread breaks when I "snap" it in place through the open eye.
Hard to explain the how, but I solved that by holding the thread and needle a bit differently and the problem seems to go away. So when it the thread breaks, I just have to jog my memory on my self-discovery on the how-to!
Agree with others ... the self-threaders seem to max out as the thread thickens.
Surely ... there are different size needles for coarser thread, and we have not found them.
Does anyone know the answer to that?