Recount is very good, and very user friendly. You can set it up to record pet damage seperately, or merged with hunter/lock/mage etc.
We have 2 guys that run with us that use different meters than Recount, but they don't report DPS - just total damage. But we find that our numbers are usually the same. If someone is reporting VAST differences in damage... especially reports that put them higher on the chart, they either have a smaller recording radius (Recount defaults at 200 yards. Some may only record within 10 yards), or they failed to reset the meter before the run. A guildie even ditched one of his meters (don't know which one) because it was recording lock's drain life as healing - and not factoring it into damage.
Recount can also report single fight stats. It keeps those single fight stats for 5 fights. This way, you don't have to reset before a boss fight if you want to see that fight alone.
Either way, there's no 100% accurate meter, and they only paint a picture, They shouldn't be used for trashing players (as long as you're killing the bosses just fine, it really doesn't matter). But if you're having trouble, and feel you don't have enough DPS, they can help your raid see where you might be lacking.
Also, keep in mind that certain fights make accurate measures of DPS difficult, and/or make certain classes really rock the charts. A lock on Illhoof, for example, will register incredible amounts of damage, but will never come close to that on other fights.
Edited, Jan 29th 2008 3:33pm by Steelray