Oh yes i picked this ring up from a normal run, and i also honoured it with my +22 healing gem. All in all a brilliant ring.
I mean having both int and stamina with a total of 70 healing makes it very powerful, and thats before you take a look at the haste. 14 spell haste is almost 1% at level 70 (lets assume it is 1% for a moment).

so assuming it affects your casting spells directly that would mean a 3 second cast would be brought down to being a 2.97 seconds cast, not a massive or impressive difference imo.

I think that haste is one of those stats that only becomes really useful if you stack alot of it, like armour ignore.

In alot of the current endgame content (BT/MH/SW) you start to see more spell haste drops, and i think if you are at this stage in the game as a healer then you can start to think about stacking it, before that i really dont see much of a point to it, especially since items with spell haste outside of these places are few and far between.

Now the main reason why i have decided to keep this ring in my bags and not one of my equip slots is that it doesnt have any mp5, and mp5 is king in my book for a holy paladin. Also the ring doesnt have any spirit which i know is what priests and druids need for their mana generation.
In the 10 man raids and all 25 mans you will start to see how useful mp5 is.
With my point of view on mp5 there are alot better rings out there that imo you can get quite easily if you are capable of killing kael'thas in normal.
I use http://thottbot.com/i29373 and also an identical ring which dropped from the headless horseman during last halloween.
If you take a quick look youll see in comparison to kharmaa's ring my band of halos has 7 more int, the same stamina (after socket bonus), 2 less healing and my fav - 6Mp5. But ofcourse it doesnt have a gem socket.
So ask yourself can a single gem socket contend vs 7int and 6mp5, and if you're anything like me you'll say no, there arent any gems that are that powerful.

So in short i think that Kharmaa's ring is very nice to have, but it can beat beat quite easily :)

Mex - Kilrogg
Have fun.