The Spirit Realm

The numbers for you assuming you have Mana Preservation V and Qvic Gloves and Arms.

Yoppa's Mending
Base Cost: 691 mana
Adjusted Cost: 691 * .95 = 656 mana (average)
Average Heal: 3714
Max Heal: 4270

Daluda's Mending
Base Cost: 607 mana
Adjusted Cost: 607 * .875 = 531 mana (average)
Average Heal: 3227
Max Heal: 3709

The Difference
Base Cost: 84 mana
Adjusted Cost: 125 mana (average)
Average Heal: 487
Max Heal: 561

My opinion: I'd only ever use Daluda's with that focus if I was PLing a toon where Daluda's is a CH. By the time your guild is into Qvic, you should almost never be running out of mana. Tanks running out of health is always a problem. Go with the bigger heal and enjoy the stats and mod2 on your gloves, they are far superior to the crappy melee effects we got on the Time gloves.

Using Daludas is only ever apropriate when you are powerlevelling people less then 60 IMO. For everything else use Yoppa's.

Mana is not the issue. Heal per Second is the issue. Yoppa's is significantly better than Daluda's

Actually, if your ever in a situation where you need to chain spam heal over a extended period then Daludas makes a diff. Many times you are just topping off a tank and therefore max heal is not as important then efficiency.

ATTACK OF THE NITPICKER POLICE!!

You're missing 20% flat pres from Specialization Alteration (200) [and possibly 1.25% more from CoA hat] and Spell Casting Mastery 3 AA adjustments to mana cost, and +53% fixed adjustment to heals from AA. Consult http://samanna.net/sham.info/healing.shtml for healing values. These modifiers have the effect of amplifying the differences in base costs & healing. The better AA-ed out a shm is, the better good spells are for them.

You might hate it, but it has done wonders for shaman healing for those that have completed the quest. It's better than what we had before for group HoT.