I decided to stick with factory coolant in all new vehicles and change coolant more often, like every 2 years or 30K miles.
2004 Honda Element.. 50/50 Honda Coolant/ distilled water
2005 Subaru Outback 2.5i... 50/50 Subaru Coolant + Subaru additve/ distilled water
2005 Chevy Silverado 2500HD Duramax... 50/50 Dexcool/ distilled water
[ I'd consider getting rid of Dexcool in the Silverado, but will probably just change more frequently and watch levels ]
1996 Chevy Corsica ... 50/50 Dexcool/ distilled water
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In my older German cars I use G05
1995 BMW 325ic ... 50/50 G05 / distilled water
1986 BMW 325es ... 50/50 G05 / distilled water