Energie Charges Uniques

Good evening,

i am playing atm a Frost Monk lvl 33. I found two Monk uniques 1. Shoes with +1 max Energy Charges and 8% Critbonus for each charge. 2. Chest with 20% chance to get a energy charge and if i get the maximum of charges they will disappear and my character get shocked. I skilled "Resonance" in the passives and i will get then as i understand endurance charges for my energy charges. But i don´t really understand if the uniques are usefull and help me or if they are just trash. Please help me to understand them better.

Greetings