I’m only half joking when I say that Eight Sleep’s temperature-controlling mattress cover improved my marriage. A good night’s sleep is elusive in my house. I’m always cold, my spouse runs hot. We battle nightly over the thermostat. So when I first reviewed an Eight Sleep cover, it was a revelation. I could curl up and drift off into a toasty slumber. My spouse could make like a penguin and sleep on a slab of ice.
The only thing I didn’t like was the nearly $1,900 price and the…