I would beg to disagree with you Tom. I think that if Garrett or Borg Warner or whoever put a cooled CHRA on a turbo, they would very much say you must use them, at least if you value the warranty. Just because older turbos didn't have cooled CHRA's and lived, doesn't mean that you should disregard them when they're present. What do you gain by not using them? Faster install?