most efficient way of populating a combobox (in maya)

[astan.chee Astan]

Hi,
I'm making a GUI in maya using python only and I'm trying to see which
is more efficient. I'm trying to populate an optionMenuGrp / combo box
whose contents come from os.listdir(folder). Now this is fine if the
folder isn't that full but the folder has a few hundred items (almost
in the thousands), it is also on the (work) network and people are
constantly reading from it as well. Now I'm trying to write the GUI so
that it makes the interface, and using threading - Thread, populate
the box. Is this a good idea? Has anyone done this before and have
experience with any limitations on it? Is the performance not
significant?
Thanks for any advice