With a 3% ssr draw rate, a 50% chance of those being eidolons bringing the weapons down to 1.5%, and less kami than ssr weapons the likelihood of drawing a single ssr kami is as bad as fkg rainbow draw rates. Trying to get two of them means you've got almost literally like .5% OF a .5% chance of actually getting that, much less two you would want together. That's a .0025% chance. Personally, I think people just get lucky on rolls.