There are many brands that rebuild the Denso cores and they are available from almost anywhere. If a remanufacturer does a quality job using quality parts, then these units will last ~100k miles/10 years or so. Ones remanufactured with questionable workmanship and/or questionable parts are iffy and on average only last 10-20k miles or 1-2 years. Denso units were top notch, so while they were available these were the ones to get. There may be other rebuilds that rival Denso, but I don't know which ones they are. I'm guessing the more expensive options are likely better, but who really knows.........If anybody has good luck with another brand please let us know. Tim
PS: If/when the Denso units are gone it might be worth upgrading to a Delco Remy CS-144 alternator like I did HERE. Tim