[HummerRidin26"kmc's]

i have had some serious issues with my steering, hub assemblys,abs system, just all kinds of ****. Well my wheel hubs are out again so i called gm an they wanna charge 550 bucks per hub. i thought that was quite umm insane. Just wonderin what you guys thought on a hub choice an will a aftermarket hub work?? The last aftermarket hubs i bought from orileys didnt do all so hot the speed sensors where causing the traction control to kick in. Where can i get hubs cheaper? my dealership said they had to be actully Genuine GM made hubs not so sure i believe that but??? thanks for your time