I feel just fine about it. In fact, I prefer that Blizzard does not implement RDF. I will explain why later below.
This is a one-button feature. It would depend on the role you play. Again, I will expand on this later below.
In my opinion, the negatives far outweigh the positives. See below for more detail.
Detailed explanation:
In my opinion, RDF was an idea that was implemented but at a cost. At first it seemed like a good idea but then something happened. I am not going to lie. It was neat being put in a group with other people from other servers but then instead of a name, instead of a character, you became nothing. Instead of a community of people who you leveled with, who you ran dungeons with, who you talked to, interacted with, who you role played with and talked with were quickly dashed away. You became a random stranger and no one cared about anyone except themselves. And if you disagreed? You got kicked. In other words this was a feature where Blizzard alienated its customers.
The only positive that I can come up with for RDF is that it was something that players could easily and quickly access with the stroke of one button.
The negatives? Well. In addition to what I mentioned in the first paragraph, if you played the role of a Tank, your wait in the queue was extremely, very short. Which in turn meant you could run more dungeons. Which also in turn meant that you could earn more badges which you could turn in for gear or other items. ie: It rained all kinds of success if you played a tank. You could make tons of gold, obtain gear, heirlooms, rep tokens, all kinds of stuff.
If you played a healer? Your wait in the queue was, in my experience not nearly as short as the tank but it was still efficient enough.
If you played as a DPS? Good luck! Your wait in the queue was extremely very long. I hope you like sitting there doing nothing. You keep mousing over the dungeon finder eye hoping to see that a tank or heals has filled its spot. Nope. Darn. 30 minutes pass by. 45 minutes pass by. 60 minutes pass by. You let out a sigh and decide to rethink if RDF was really such a good idea…and then you wonder “Why didn’t I just roll a tank when they have short queue times but I don’t want to tank. I want to DPS. But I have to wait. Nope.” Then you log off.