Very hard to compare because it's usual - indeed basically mandatory - to climb Everest as a group whereas it's forbidden to attempt these ultra races in that way, the competitors aren't even allowed to help each other during a loop.

Also they're not kidding about Everest's death zone - it's genuinely incompatible with human life up on that mountain, whereas while its no stroll in the park where this race is held, it's not going to just kill you if you stay there a bit longer - the strict timer is because many more people could complete the loops at a slower pace. Not me, but probably most serious entrants.