So many of my friends IRL and online have "converted" after being stubbornly against 4e for many months when it was published.
My opinion hasnt changed. Pretty much everything that they have done in 4e is pretty much the opposite of the way I would have done it.
But I DM it. One thing that they really nailed was how to make the game easier on the DM. As in less than 10% the effort for better adventures.
But to answer the OP: TURN UNDEAD YOU FOUL THREAD ZOMBIE!!!.....wait, I mean, as a product, they are still a bit off the mark, and I am pretty close to the end of what I am going to buy. For 3e there were two of us who bought all the products, and nearly everyone else the core 3. For 4e, only 1 buys all, one buys some, and not even everyone bought the PHB1.
Did anyone buy the DI?
Did anyone buy the DI?
Did anyone buy the DI?
Necessary? Absolutely not. I played in three different campaigns without it and didn't feel the lack. Because most of the characters I played didn't have supporting books that I didn't own.No one in my play group has DI, and we have not missed it at all. Making up characters with the books we have takes some time, for sure, but when the character is done, I feel we know it well. If I whipped one up in a few minutes, would I know what the character is? I've seen a lot of people make up a lot of characters for my PBEMs on a huge variety of characer generators and then have no idea how to play them or what their characters could do.
I'm willing to admit DI could be a good tool, but I remain unconvinced it is necessary to play 4E.