Soda Jack - I've had nothing but very positive experiences with Destiny LFG, I've used it for probably 12+ raids, a couple nightfall strikes, and a couple weekly's.
Everybody's been very mature, friendly, helpful, and we've been successful all but a couple of times. I'm honestly quite shocked. I've played with over 70 people and none of them fell into any of the negative stereotypical categories of gamers. But I guess that's what happens when you have people with mutual goals that could get booted by the host if they act up or easily leave the game if the host is a douche.
Whereas in matchmaking, people are random, can't get booted, won't play with/against their teammates/enemies again, and don't always have a common goal in mind. It would be nice to see the revival of a server browser or an in game system similar to Destiny LFG as a secondary system to matchmaking. I feel like this would help mitigate the bad people.