I have used Warn's hubs on my '94 V6 with ADD for many years. I have heard that the OEM manual hubs may be stronger. I do moderate 4 wheeling and haven't had any problems with this setup. I never noticed any significant change in mileage.

I think this setup is better than original since the axles aren't turning all the time, which is easier on the CV joint's and CV boots since I use lowered bumpstops and keep the torsion bars cranked up a little bit.