4600 bilsteins on my 04 at about 5,000 miles because I wasn't happy with the factory shocks. they are still working well at 125K (son now has the truck)
2015 Denali 2500, first tow with factory shocks and again, bilstein 4600 ordered and installed, much improved.
04 also has the bilstein steering stabilizer replacing the stock one at 125K miles. Not as much improvement noticed. stock one had the rubber bushing worn out and was clunking. Need a good pickle fork to get the steering stabilizer off on the 04.