"normal balls sometimes working better than ultra balls" can easily be explained by rolling a six sided die vs a 100 sided die. If the number you want is 6 and you roll the six sided die three times and don't roll a 6, but roll the 100 sided die once and immediately get 6, that's not the 100 sided die being more likely to roll a 6, that's literally just how statistics works. Just because you happen to occasionally have better luck with something that's statistically worse doesn't make it better.