Got my coolant test results back today. Good news I believe. Report stated "No action required' and 'test results normal'. 'Re-sample at next engine service'. Here are the numbers I got back
Metals ppm     BP     FP     GL     ph     Con
                     108   -42    53     8.5    3224
Other             NO2      odor      Ctype      color      app      foam      oil
                    1760     norm     conv        green     clear    norm      none
The test was done through Holt CAT in Stockton CA. We talked for a few minutes. He said ELC was 6 years, 600,000 miles. Regular (like mine) was 3 years 3,000 hours. My engine is at about 1200 hrs. Said I was good to go. 
I have gotten a few prices for drain/refill. Bossleman was $285 to drain/flush/refill with ELC. Drain/flush/refill with regular HD coolant was $230. ELC seems the way to go, $55 for an additional 3 years. 
Thoughts?
Ken 2007 Contessa