2C-E > 2C-B
2C-E passes 2C-B right on by, and leaves it in the dust. But I think it all depends on what you are looking for in a psychedelic.
To me, 2C-B feels great and is a lot of fun. But it is totally lacking in depth and meaning when compared to 2C-E. Even at dosages above 30mg, I do not find 2C-B all that challenging. At just 16mg however, 2C-E had depth that compared easily (for me) with LSD.
It has been a year and a half, since my last 2C-E trip and I am still reaping rewards from it, and still in awe of what happened. My last 2C-B trip (which was in August) was great, lots of fun, but still largely forgettable (as most of my 2C-B trips have been.)
The thing 2C-B has going for it, is how easy it is to take. Nice, short trip with great visuals and a wonderful body-high. 2C-E may have a few more body-kinks, and may not be quite as jolly as 2C-B...but I sure take home much more in the long run from it.
2C-B is a great all-purpose psychedelic, and I'd be comfortable using it a few times a year for a number of reasons. 2C-E is something I only need once in a good, long while. And 2C-E is something I could only take in the most pristine, gentle settings. So much happens with that one, you really have to be careful about where, when, and with who.