The magnetic cable (plugged into the OEM brick) was provided by the company because people who had been using MagSafe macbooks for a decade or more kept damaging their Thunderbolt ports when they jerked the cable out accidentally. I don't have a magnetic cable at home, just the cable that came with the OWC docking station that my girlfriend bought a few years ago for her 12" MacBook but doesn't use.
I won't be back to the office until Thursday but I just noticed that using the new MacBook at home all-day on Friday it didn't kernel panic once.