For the 25 years I have been working on cars, I have installed almost nothing but Delco and have had great success. I've only had a couple that died early, and a couple go 8+ years. I've probbaly installed close to fifty of them, but since GM dumped them off to Delphi, and Delphi sold them to Johnson Controls, I can't really say whether they are still as good as they were. I don't know if JC builds all their batteries to the same spec, or if it depends on what brand they are. I know a few people were put off on Delco batteries because the original ones in their cars didn't last real long, but if you notice, GM NEVER put their best batteries in OEM applications. Unless It's for a car I know won't be around much longer, I always buy the largest, most powerful, longest lasting battery I can shoehorn into the vehicle. (usually a 78DT84 dual terminal.)