Hello Rathi,
Yes you are correct
But, SORT propertoy of ordinary Combobox control has another very significant advantage -
incremental search.
Practically, in most of my apps, aSort() function or "ORDER BY" clause in SQL - send sorted arrays to Grid Comboboxes. But, there is no incremental search like your achoice code or CSB. Achoice or CSB is more advanced in the sense that 1) we can edit text box value, 2) value is text not integer and 3) we can have a choice of without selecting any item.
Again, if we have sort property in Grid Combobox control, incremental search will be very easy. If not possible, no problem -you already showed us how to use achoice with Grid
BTW, I also use Grid control itself (not celled) for incremental search

And after recent experiment with browse control, I found, this cannot be done with Browse - where record pointer cannot be changed without using Arrow keys or mouse click.

(and for that reason, onece I requested Roberto for
non-celled grid
with table)