What may dog you finding a site with uptimes is that such can be damned since one user will have an issue that takes months to fix and another like me has some uninterrupted usage for years.
So let's call it 99%?
We have a MAC/PC household and are ready to switch away from Earthlink DSL to either AT&T DSL or Comcast cable. I can't find any uptime/reliability data that compares the two.

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