For healers you have to set up a team. What do I want on my team? Variety is nice. Access to different abilities and cooldowns is a plus. Fitting each healer's niche in, and having healers cover each other's weaknesses.
Stuff like this is why we still use restoshamans, druids, holypriests and monks instead of stacking paladins and disc priests. While damae reduction/prevention from pallies and priests are really nice and their hps is inflated because of it, Paladins and disc priests just don't have the "healing" capabilities of other classes.
Druid hots are an amazing healing buffer and are great are recovering damage quickly. Disc priests don't have a single ability that works like a resto druid's hots. So while disc has higher hps, you still want to bring your resto druid along side your disc priest. Understand?
Its like this for all healers. Shamans have amazing cooldowns, (and manatide is godly), monks are an excellent source of damage with high healing and a very good cooldown. Resto druids and holy priests are both very similar, their hots and instant casts are very good and their healing cooldown is phenomenal.
Back to the original question though, do meters matter? Yes they do. But when you're comparing healers, its best to compare people of the same class in terms of healing done and hps. Its just unrealistic to compare the holy paladin to the resto shaman, especially when there are so many fights that differentiate in which healing class they cater to.
I hope my long rant helps!
edit: I hope nobody uses what I said as an excuse for low healing