I did oil analysis on my 2003 truck, mostly because I bought it used and wanted to check for any problems. As a result of sampling I was able to increase the miles between oil changes. I originally was changing at 6k mile intervals, but increased to 8k, then 10k, then 12k miles. I used regular Rotella and Fleetguard filters.
I used Blackstone for the analysis and they recommended extending the oil change intervals. So I saved enough on oil and filters to more than pay for the analysis costs. The oil analysis info was a selling point when I sold my truck also. I had a total of six samples analyzed at a cost of about $140. I saved about 35 oil changes at a cost of about $35 each, or a total of $1225. For me it was well worth it, but I put a lot of miles on the truck.