Gold Kits have 30% For Legendary, 5% Mythical and Epic/Rare I do not know.
Gold Kits Improve your chance to get Legendary and Really Good Weapons and Items.
It dosnt ALWAYS Give you a Good Item or Weapon, It increases your chance to get something good. I guess you just got a really bad Box. But, At the same time i would treasure that Lot you got. Because The Kits. Especially Ressistence ones. Imagine going into battle with your mech on 23 Ressistence then adding 22 to it? Thats 45 Ressistence. It will Help you go far!
And if they are Weak weapons/Weapons or kits you dont want, Fuse it into your torso,Legs or Weapons. It may not upgrade it straight away but it will chip bits off if. so your closer and closer. Just Fuse them or use the Kits if you dont like them, They do help.

Yes, kits suck!

I got tons of useless kits out of boxes. I got one gold box too, because of a friend. 4 useless kits and one weapon.

Kits are too heavy and give not enough power to be usefull, .

i agree with this, either add legendary and mythic kits or remove them from the gold and silver boxes.

Hope you guys have reconsidered, They are now weightless, Yess you can only hold two but better than using up 120 weight on two of them, I love it honestly, I am always keen on getting Kits from boxes (:

The disappointing factor of getting kits from gold item boxes is the fact that you can get them from normal item boxes quite easily. There is higher chance of getting a rare item from a normal item box then any other tier, and from the rare tier kits are abundant. Sure, they are useful, but consumable and common. What people really want from Gold Boxes are non-consumables. The chances of getting something legendary or mythical is already weighed down by tons of rare and epic item chances, and getting a golden box that is consisting of more than one kit is like a slap in the face. Honestly, I believe that gold boxes are something that should become kit free.