I would go with an OEM part, unless you plan on racing or something like that. Fluid and filter are the only maintenance it should need.
My 91 MJ had the AW4 but the only thing I ever did to it was change the fluid / filter. It is made by Aisin (Toyota) so they are very reliable.
My 91 MJ had the AW4 but the only thing I ever did to it was change the fluid / filter. It is made by Aisin (Toyota) so they are very reliable.