It is late so I would be brief first, might add more later. Figured this might be useful considering I don't even know.
I personally find that Resto Staff is superior for ranged staff DPS compared to Destruction Staff. I was researching on my Sorc class builds, and I came upon some builds that use Restoration Staff. I found out some interesting information that I didn't know about. Later on Denny's Deshaan Smash and Grab, Denny confirmed it and provided even more usage of Resto Staff. Thanks for the confirmation.
Resto Staff has a *hidden* bonus - It restores 10% magicka on every heavy attack.
Now I don't know of what hidden bonuses destro staff has, but I read that it *might* have slightly higher dps. But don't quote me on that. As a Sorc and heavy magicka usage, I find that the Resto Staff is superior! I have been using Destro Staff so far, but actually I don't really need it except for casting occasional Elemental Wall. My class spells are generally more useful. Not sure about other classes though.
Resto Staff also has very strong synergy with passives that will benefit your overall character.
- Essence Drain - 2/2 - Final attack heals 30% of damage done
- Cycle of Life - 2/2 - Deals 1% damage for every 10% life you have for total bonus 10% dmg bonus
- Absorb - 2/2 - Blocking spells restores magicka. Esp good for tank
If you are healing, the other passives are great. But the passives are very useful both in soloing and group. So always try to cast your Resto Staff heavy attack. You can still cast other spells in between and it will always supersede your heavy attack.
Hope this is useful information. Does anyone knows the benefits of destro staff? (Outside of specific preference for certain desto staff skills or simply would like the tri-elemental dmg)
TL;DR While doing "auto attack", you are healing your group, increasing your base DPS, restoring your own magicka and at the same time casting your other class spells.