I didn't know you can have legendary with this perk
(In my first playtrought (day one), i have this perk but never had a legendary at all (plenty of uncommon, rare and epic).
The only legendary, i had is system reset, but it's during "Spellbound")
But it's :
Increase the chance of getting QH of 50%-100% (and not 50% or 100% to get one).
Base chance is pretty low... (ex: if you have 2% chance to get one. with this perk lvl 2, you "only" have 4%...).
In my opinion, this perk is only usefull if you stay at lvl 12 in INT (no be able to craft epic). If you're lucky (and hack large amount of acces point), you can eventually get epic QH. But if you play as hacker, you must craft your QH