Most people seem to decide whether they should take an item based on the following check list; Is it epic? Does it increase my overall gearscore/does it have a higher itemlevel than my current gearpiece? If the answer is yes to one or both of these criteria, then they will need the item. There isn't anything generally wrong with this procedure as it will most of the time reward you with a better item than your current.
Epics, gearscore and high ilevels do look pretty when people inspect you. I actually know alot of people who equip a ludicrous mix of items for when they're random pugging, just to look good on the outside. But there are plenty of items out there that rock ass, eventhough they're not of high ilevel (high is always relative of course, currently that would be around 232+) or even epic. Rough diamonds if you like, that can shine if you give them the chance.
One such item is Spark of Life (EDIT: Added link), that drops from Sjonnir the Ironshaper (the last boss) in heroic Halls of Stone. It is a trinket, and good trinkets could be hard to come by overall. It doesn't look like much, it is of blue quality and only has ilevel 200. So why on Azeroth would you want to equip such an item? What makes this trinket so good is that it provides a really nice amount of haste - 73 rating to be exact. At level 80 that is 2,23% (according to wowhead.com). The second mechanic gives an overall mp5 of between 42-50mp5, depending on your spell cast style. That too is a great amount. Compare that to the normal version of Sliver of Pure Ice which has an ilevel of 251 and requires you to raid to acquire. It has an average of 75mp5, which also isn't passive like in Spark of Life.
What makes this trinket so special? Well it is actually the only haste trinket available, that is also useful for healers. Every other trinket has a second mechanic that only works either for caster dps or melee/ranged dps. Haste is an awesome stat for healers, regardless of class most healers seek to get above 20% haste, at least. So it is quite strange that there are no more haste trinkets out there that aren't designed solely for dpsers. There are two pvp-trinkets that could work for healers as well, as one increases health and the other removes movement impairing effects. But these mechanics are not something you'd usually find useful in a pve-setting.
So if you want a good chunk of haste, and you're a healer - Spark of Life is where you'll have to go.