In practice, not so much, especially if you like to sleep and wake up from sleep everytime without a crash + a reasonable power consumption, both during use and during sleep.
IMHO consumption during sleep far more important: if I didn't plug the computer, I expect it to wake up immediately (no S4/suspend to disk) and with less than 0.5% of battery lost per hour (so for 10h of sleep and 80% battery before sleep, at least 75% battery left), if I put it in a bag, I expect it to stay asleep and not be a fire hazard: dells run hot when closed and in a bag, to the point of battery exhaustion or thermal shutdown)
I prefer Lenovo for everything, especially the keyboard but also ECC ram, OLED displays ... things almost impossible to find anywhere else!
I've been moving to a eink tablet but I purchased a Lenovo wireless keyboard: every key being in the exact same position on all my hardware has sizeable benefits in comfort.
Also, I want PageUp and PageDown around the Up key, something impossible to find outside of Lenovo.