I'm sure they've fixed the problems by now, but Fastmail has the distinction of being the only email service that ever locked me out of my email for five consecutive days (along with many, many other users), with one hapless support guy trying to fix it while the then-owner (who built the damn thing) was nowhere to be found. I am always vastly amused when people rave about it.

Meanwhile, Gmail has never lost a single email of mine dating back 14 years.

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